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title: 'JAVADOC(1) JDK @@VERSION_SHORT@@ | JDK Commands'
date: @@COPYRIGHT_YEAR@@
lang: en
---

## Name

javadoc - generate HTML pages of API documentation from Java source files

## Synopsis

`javadoc` \[*options*\] \[*packagenames*\] \[*sourcefiles*\] \[`@`*files*\]

*options*
:   Specifies command-line options, separated by spaces. See [Standard `javadoc`
    Options], [Extra `javadoc` Options], [Standard Options for the Standard Doclet],
    and [Extra Options for the Standard Doclet].

*packagenames*
:   Specifies names of packages that you want to document, separated by spaces,
    for example `java.lang java.lang.reflect java.awt`. If you want to also
    document the subpackages, then use the `-subpackages` option to specify the
    packages.

    By default, `javadoc` looks for the specified packages in the current
    directory and subdirectories. Use the `-sourcepath` option to specify the
    list of directories where to look for packages.

*sourcefiles*
:   Specifies names of Java source files that you want to document, separated
    by spaces, for example `Class.java Object.java Button.java`. By default,
    `javadoc` looks for the specified classes in the current directory.
    However, you can specify the full path to the class file and use wildcard
    characters, for example `/home/src/java/awt/Graphics*.java`. You can also
    specify the path relative to the current directory.

`@`*files*
:   Specifies names of files that contain a list of `javadoc` tool options,
    package names, and source file names in any order.

## Description

The `javadoc` tool parses the declarations and documentation comments in a set
of Java source files and processes them using a pluggable back-end called a
[_doclet_][doclet].

The [_standard doclet_][standard-doclet] is the one that is used by default,
and can produce corresponding HTML pages that describe the public and protected
classes, nested and implicitly declared classes (but not anonymous inner classes),
interfaces, constructors, methods, and fields. The standard doclet interprets
the content of documentation comments according to the
[JavaDoc Documentation Comment Specification for the Standard Doclet][doc-comment-spec].
Custom tags in documentation comments are supported by means of [taglets][taglet].

You can use the `javadoc` tool and the standard doclet to generate the API
documentation or the implementation documentation for a set of source files.

You can run the `javadoc` tool on entire packages, individual source files, or
both. When documenting entire packages, you can use the `-subpackages` option
either to recursively traverse a directory and its subdirectories, or to pass
in an explicit list of package names. When you document individual source
files, pass in a list of Java source file names.

### Documentation Comments

The `javadoc` tool uses the documentation comment, if any, that immediately
precedes the beginning of the declaration, whether that is an annotation,
modifier, or the name being declared. If there are multiple documentation
comments before the declaration, only the last one (closest to the declaration)
will be used.  If there are any documentation comments after the beginning of
the declaration, they will be ignored.  To check for any extra or misplaced
documentation comments, compile your source code with the `javac` option
`-Xlint`, or more specifically, `-Xlint:dangling-doc-comments`. Within a
source file, you may suppress any warnings generated by these options
by using `@SuppressWarnings("dangling-doc-comments")` on a suitable enclosing
declaration.

[doc-comment-spec]: ../javadoc/doc-comment-spec.html
[doclet]: ../../api/jdk.javadoc/jdk/javadoc/doclet/Doclet.html
[standard-doclet]: ../../api/jdk.javadoc/jdk/javadoc/doclet/StandardDoclet.html
[taglet]: ../../api/jdk.javadoc/jdk/javadoc/doclet/Taglet.html

### Conformance

The standard doclet does not validate the content of documentation comments for
conformance, nor does it attempt to correct any errors in documentation
comments. Anyone running javadoc is advised to be aware of the problems that
may arise when generating non-conformant output or output containing executable
content, such as JavaScript. The standard doclet does provide the [DocLint](#doclint)
feature to help developers detect common problems in documentation comments;
but it is also recommended to check the generated output with any appropriate
conformance and other checking tools.

For more details on the conformance requirements for HTML5 documents, see
[Conformance requirements for authors](
https://html.spec.whatwg.org/multipage/introduction.html#conformance-requirements-for-authors)
in the HTML5 Specification. For more details on security issues related to web
pages, see the [Open Web Application Security Project (OWASP)](
https://www.owasp.org) page.

## Options

`javadoc` supports command-line options for both the main `javadoc` tool
and the currently selected doclet. The standard doclet is used if no other
doclet is specified.

GNU-style options (that is, those beginning with `--`) can use an equal sign
(`=`) instead of whitespace characters to separate the name of an option from
its value.

### Standard `javadoc` Options

The following core `javadoc` options are equivalent to corresponding `javac`
options. See *Standard Options* in [javac](javac.html) for the detailed
descriptions of using these options:

* <span id="option-add-modules">`--add-modules`</span>
* <span id="option-bootclasspath">`-bootclasspath`</span>
* <span id="option-class-path">`--class-path`, `-classpath`, or `-cp`</span>
* <span id="option-disable-line-doc-comments">`--disable-line-doc-comments`</span>
* <span id="option-enable-preview">`--enable-preview`</span>
* <span id="option-encoding">`-encoding`</span>
* <span id="option-extdirs">`-extdirs`</span>
* <span id="option-limit-modules">`--limit-modules`</span>
* <span id="option-module">`--module`</span>
* <span id="option-module-path">`--module-path` or `-p`</span>
* <span id="option-module-source-path">`--module-source-path`</span>
* <span id="option-release">`--release`</span>
* <span id="option-source">`--source` or `-source`</span>
* <span id="option-source-path">`--source-path` or `-sourcepath`</span>
* <span id="option-system">`--system`</span>
* <span id="option-upgrade-module-path">`--upgrade-module-path`</span>

The following options are the core `javadoc` options that are not equivalent to
a corresponding `javac` option:

<span id="option-breakiterator">`-breakiterator`</span>
:   Computes the first sentence of the description in a documentation comment
    using an instance of `java.text.BreakIterator` to detect _sentence breaks_.
    The rules that are used depend on the [current locale](#option-locale):
    for example, for English, a sentence break occurs after a period, question mark,
    or exclamation point followed by a space when the next word starts with a
    capital letter. (This is meant to handle most abbreviations, such as
    "The serial no. is valid", but will not handle "Mr. Smith".)

    The option is enabled by default if the language of the current locale is
    not English. If the language of the current locale is English, and the
    `-breakiterator` option is not given, a simple default algorithm is used,
    which just looks for a period followed by a space.

    In a traditional `/**...*/` comment, the search for the end of the first
    sentence is terminated by an HTML block tag, such as `<p>`, `<pre>`, or
    the tag for a heading.

    In a Markdown `///` comment, the search for the end of the first sentence
    skips over any characters enclosed in code spans and links, and is
    terminated by the end of the initial block, as indicated by a
    blank line or the beginning of the next block, such as a list, thematic break,
    or an HTML block.

    The first sentence of the description in a documentation comment is used in
    summary tables, index pages, and other situations where a short summary is
    required. For more explicit control in any individual documentation comment,
    enclose the contents of the first sentence in a `{@summary ...}` tag, or
    when applicable, in a `{@return ...}` tag.

<span id="option-doclet">`-doclet` *class*</span>
:   Generates output by using an alternate doclet. Use the fully qualified
    name. This doclet defines the content and formats the output. If the
    `-doclet` option isn't used, then the `javadoc` tool uses the standard
    doclet for generating the default HTML format. This class must implement
    the `jdk.javadoc.doclet.Doclet` interface. The path to this class is
    defined by the `-docletpath` option.

<span id="option-docletpath">`-docletpath` *path*</span>
:   Specifies where to find doclet class files (specified with the `-doclet`
    option) and any JAR files it depends on. If the starting class file is in a
    JAR file, then this option specifies the path to that JAR file. You can
    specify an absolute path or a path relative to the current directory. If
    `path` contains multiple paths or JAR files, then they should be
    separated with a colon (`:`) on Linux and macOS, and a semicolon (`;`) on
    Windows. This option isn't necessary when the `doclet` starting class is
    already in the search path.

<span id="option-exclude">`-exclude` *pkglist*</span>
:   Unconditionally, excludes the specified packages and their subpackages from
    the list formed by `-subpackages`. It excludes those packages even when
    they would otherwise be included by some earlier or later `-subpackages`
    option.

    The following example would include `java.io`, `java.util`, and `java.math`
    (among others), but would exclude packages rooted at `java.net` and
    `java.lang`. Notice that these examples exclude `java.lang.ref`, which is a
    subpackage of `java.lang`. Arguments are separated by colons on all
    operating systems.

    -   **Linux and macOS:**

        ```
        javadoc -sourcepath /home/user/src -subpackages java -exclude java.net:java.lang
        ```

    -   **Windows:**

        ```
        javadoc -sourcepath \user\src -subpackages java -exclude java.net:java.lang
        ```

<span id="option-expand-requires">`--expand-requires` (`transitive`|`all`)</span>
:   Instructs the javadoc tool to expand the set of modules to be documented.
    By default, only the modules given explicitly on the command line are
    documented. Supports the following values:

    -   `transitive`: additionally includes all the required transitive
        dependencies of those modules.

    -   `all`: includes all dependencies.

<span id="option-help">`--help`, `-help`, `-h`, or `-?`</span>
:   Prints a synopsis of the standard options.

<span id="option-help-extra">`--help-extra` or `-X`</span>
:   Prints a synopsis of the set of extra options.

<span id="option-J">`-J`*flag*</span>
:   Passes *flag* directly to the Java Runtime Environment (JRE) that runs the
    `javadoc` tool. For example, if you must ensure that the system sets aside
    32 MB of memory in which to process the generated documentation, then you
    would call the `-Xmx` option as follows:
    `javadoc -J-Xmx32m -J-Xms32m com.mypackage`. Be aware that `-Xms` is
    optional because it only sets the size of initial memory, which is useful
    when you know the minimum amount of memory required.

    There is no space between the `J` and the `flag`.

    Use the `-version` option to report the version of the JRE being used to
    run the `javadoc` tool.

    ```
    javadoc -J-version
    java version "17" 2021-09-14 LTS
    Java(TM) SE Runtime Environment (build 17+35-LTS-2724)
    Java HotSpot(TM) 64-Bit Server VM (build 17+35-LTS-2724, mixed mode, sharing)
    ```

<span id="option-locale">`-locale` *name*</span>
:   Specifies the locale that the `javadoc` tool uses when it generates
    documentation. The argument is the name of the locale, as described in
    `java.util.Locale` documentation, such as `en_US` (English, United States)
    or `en_US_WIN` (Windows variant).

    Specifying a locale causes the `javadoc` tool to choose the resource files
    of that locale for messages such as strings in the navigation bar, headings
    for lists and tables, help file contents, comments in the `stylesheet.css`
    file, and so on. It also specifies the sorting order for lists sorted
    alphabetically, and the sentence separator to determine the end of the
    first sentence. The `-locale` option doesn't determine the locale of the
    documentation comment text specified in the source files of the documented
    classes.

<span id="option-package">`-package`</span>
:   Shows only package, protected, and public classes and members.

<span id="option-private">`-private`</span>
:   Shows all classes and members.

<span id="option-protected">`-protected`</span>
:   Shows only protected and public classes and members. This is the default.

<span id="option-public">`-public`</span>
:   Shows only the public classes and members.

<span id="option-quiet">`-quiet`</span>
:   Shuts off messages so that only the warnings and errors appear to make them
    easier to view. It also suppresses the `version` string.

<span id="option-show-members">`--show-members` *value*</span>
:   Specifies which members (fields, methods, or constructors) are documented,
    where *value* can be any of the following:

    * `public` --- shows only public members
    * `protected` --- shows public and protected members; this is the default
    * `package` --- shows public, protected, and package members
    * `private` --- shows all members

<span id="option-show-module-contents">`--show-module-contents` *value*</span>
:   Specifies the documentation granularity of module declarations, where
    *value* can be `api` or `all`.

<span id="option-show-packages">`--show-packages` *value*</span>
:   Specifies which module packages are documented, where *value* can be
    `exported` or `all` packages.

<span id="option-show-types">`--show-types` *value*</span>
:   Specifies which types (classes, interfaces, etc.) are documented, where
    *value* can be any of the following:

    * `public` --- shows only public types
    * `protected` --- shows public and protected types; this is the default
    * `package` --- shows public, protected, and package types
    * `private` --- shows all types

<span id="option-subpackages">`-subpackages` *subpkglist*</span>
:   Generates documentation from source files in the specified packages and
    recursively in their subpackages. This option is useful when adding new
    subpackages to the source code because they are automatically included.
    Each package argument is any top-level subpackage (such as `java`) or fully
    qualified package (such as `javax.swing`) that doesn't need to contain
    source files. Arguments are separated by colons on all operating systems.
    Wild cards aren't allowed. Use `-sourcepath` to specify where to find the
    packages. This option doesn't process source files that are in the source
    tree but don't belong to the packages.

    For example, the following commands generates documentation for packages
    named `java` and `javax.swing` and all of their subpackages.

    -   **Linux and macOS:**

        ```
        javadoc -d docs -sourcepath /home/user/src -subpackages java:javax.swing
        ```

    -   **Windows:**

        ```
        javadoc -d docs -sourcepath \user\src -subpackages java:javax.swing
        ```

<span id="option-verbose">`-verbose`</span>
:   Provides more detailed messages while the `javadoc` tool runs. Without the
    `-verbose` option, messages appear for loading the source files, generating
    the documentation (one message per source file), and sorting. The
    `-verbose` option causes the printing of additional messages that specify
    the number of milliseconds to parse each Java source file.

<span id="option--version">`--version`</span>
:   Prints version information.

<span id="option-Werror">`-Werror`</span>
:   Reports an error if any warnings occur.

Note that if a Java source file contains an implicitly declared class, then
that class and its public, protected, and package members will be documented
regardless of the options such as `--show-types`, `--show-members`, `-private`,
`-protected`, `-package`, and `-public`. If  `--show-members` is specified with
value `private` or if `-private` is used then all private members of an
implicitly declared class will be documented too.

### Extra `javadoc` Options

_Note:_ The additional options for `javadoc` are subject to change without
notice.

The following additional `javadoc` options are equivalent to corresponding
`javac` options. See *Extra Options* in [javac](javac.html) for the detailed
descriptions of using these options:

* <span id="option-add-exports">`--add-exports`</span>
* <span id="option-add-reads">`--add-reads`</span>
* <span id="option-patch-module">`--patch-module`</span>
* <span id="option-Xmaxerrs">`-Xmaxerrs`</span>
* <span id="option-Xmaxwarns">`-Xmaxwarns`</span>

### Standard Options for the Standard Doclet

The following options are provided by the standard doclet.

<span id="option-add-script">`--add-script` *file*</span>
:   Adds *file* as an additional JavaScript file to the generated documentation.
    This option can be used one or more times to specify additional script
    files.

    Command-line example:

    >   `javadoc --add-script first_script.js --add-script
        second_script.js pkg_foo`

<span id="option-add-stylesheet">`--add-stylesheet` *file*</span>
:   Adds *file* as an additional stylesheet file to the generated documentation.
    This option can be used one or more times to specify additional stylesheets
    included in the documentation.

    Command-line example:

    ```
    javadoc --add-stylesheet new_stylesheet_1.css --add-stylesheet new_stylesheet_2.css pkg_foo
    ```

<span id="option-allow-script-in-comments">`--allow-script-in-comments`</span>
:   Allow JavaScript in documentation comments, and options whose value is
    _html-code_.

<span id="option-author">`-author`</span>
:   Includes the text of any `author` tags in the generated documentation.

<span id="option-bottom">`-bottom` *html-code*</span>
:   Specifies the text to be placed at the bottom of each generated page.
    The text can contain HTML tags and white space, but when it does, the text
    must be enclosed in quotation marks. Use escape characters for any internal
    quotation marks within text.

<span id="option-charset">`-charset` *name*</span>
:   Specifies the HTML character set for this document. The name should be a
    preferred MIME name as specified in the [IANA Registry, Character Sets](
    http://www.iana.org/assignments/character-sets).

    For example:

    ```
    javadoc -charset "iso-8859-1" mypackage
    ```

    This command inserts the following line, containing a
    [`meta` element](https://html.spec.whatwg.org/multipage/semantics.html#the-meta-element)
    in the head of every generated page:

    ```
    <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
    ```

<span id="option-d">`-d` *directory*</span>
:   Specifies the destination directory where the `javadoc` tool saves the
    generated HTML files. If you omit the `-d` option, then the files are saved
    to the current directory. The `directory` value can be absolute or relative
    to the current working directory. The destination directory is
    automatically created when the `javadoc` tool runs.

    -   **Linux and macOS:** For example, the following command
        generates the documentation for the package `com.mypackage` and saves
        the results in the `/user/doc/` directory:

        ```
        javadoc -d /user/doc/ com.mypackage
        ```

    -   **Windows:** For example, the following command generates the
        documentation for the package `com.mypackage` and saves the results in
        the `\user\doc\` directory:

        ```
        javadoc -d \user\doc\ com.mypackage
        ```

<span id="option-docencoding">`-docencoding` *name*</span>
:   Specifies the encoding of the generated HTML files. The name should be a
    preferred MIME name as specified in the [IANA Registry, Character Sets](
    http://www.iana.org/assignments/character-sets).

    Three options are available for use in a `javadoc` encoding command. The
    `-encoding` option is used for encoding the files read by the `javadoc`
    tool, while the `-docencoding` and `-charset` options are used for encoding
    the files written by the tool. Of the three available options, at most,
    only the input and an output encoding option are used in a single encoding
    command. If you specify both input and output encoding options in a
    command, they must be the same value. If you specify neither output option,
    it defaults to the input encoding.

    For example:

    ```
    javadoc -docencoding "iso-8859-1" mypackage
    ```

<span id="option-docfilessubdirs">`-docfilessubdirs`</span>
:   Enables deep copying of `doc-files` directories. Subdirectories and all
    contents are recursively copied to the destination. For example, the
    directory `doc-files/example/images` and all of its contents are copied.
    Use the [`-excludedocfilessubdir`](#option-excludedocfilessubdir) option to
    restrict the subdirectories to be copied.

<span id="option-doctitle">`-doctitle` *html-code*</span>
:   Specifies the title to place near the top of the overview summary file. The
    text specified in the `title` tag is placed as a centered, level-one
    heading directly beneath the navigation bar. The `title` tag can
    contain HTML tags and white space, but when it does, you must enclose the
    title in quotation marks. Additional quotation marks within the `title` tag
    must be escaped. For example,
    `javadoc -doctitle "<b>My Library</b><br>v1.0" com.mypackage`.

<span id="option-excludedocfilessubdir">`-excludedocfilessubdir` *name1*`,`*name2...*</span>
:   Excludes any subdirectories with the given names
    when recursively copying `doc-files` subdirectories.
    See [`-docfilessubdirs`](#option-docfilessubdirs).
    For historical reasons, `:` can be used anywhere in the argument as a
    separator instead of `,`.

<span id="option-footer">`-footer` *html-code*</span>
:   This option is no longer supported and reports a warning.

<span id="option-group">`-group` *name* *g1*`,`*g2...*</span>
:   Group the specified packages, or modules when documenting modular code,
    together in the Overview page.
    For historical reasons, `:` can be used as a separator anywhere in the
    argument instead of `,`.

<span id="option-header">`-header` *html-code*</span>
:   Specifies the header text to be placed at the top of each output file. The
    header is placed to the right of the navigation bar. The `header` can
    contain HTML tags and white space, but when it does, the `header` must be
    enclosed in quotation marks. Use escape characters for internal quotation
    marks within a header. For example,
    `javadoc -header "<b>My Library</b><br>v1.0" com.mypackage`.

<span id="option-helpfile">`-helpfile` *filename*</span>
:   Specifies a file containing the text that will be displayed when the
    **HELP** link in the navigation bar is clicked. If this option is not given,
    the `javadoc` tool creates a default page that will be used.

<span id="option-html5">`-html5`</span>
:   This option is a no-op and is just retained for backwards compatibility.

<span id="option-javafx">`--javafx` or `-javafx`</span>
:   Enables JavaFX functionality. This option is enabled by default if the
    JavaFX library classes are detected on the module path.

<span id="option-keywords">`-keywords`</span>
:   Adds HTML keyword `<meta>` tags to the generated file for each class. These
    tags can help search engines that look for `<meta>` tags find the pages.
    Most search engines that search the entire Internet don't look at `<meta>`
    tags, because pages can misuse them. Search engines offered by companies
    that confine their searches to their own website can benefit by looking at
    `<meta>` tags. The `<meta>` tags include the fully qualified name of the
    class and the unqualified names of the fields and methods. Constructors
    aren't included because they are identical to the class name. For example,
    the page for the class `String` includes these keywords:

    ```
    <meta name="keywords" content="java.lang.String class">
    <meta name="keywords" content="CASE_INSENSITIVE_ORDER">
    <meta name="keywords" content="length()">
    <meta name="keywords" content="isEmpty()">
    ```

<span id="option-link">`-link` *url*</span>
:   Creates links to existing `javadoc` generated documentation of externally
    referenced classes. The *url* argument is the absolute or relative URL of
    the directory that contains the external `javadoc` generated documentation.
    You can specify multiple `-link` options in a specified `javadoc` tool run
    to link to multiple documents.

    Either a `package-list` or an `element-list` file must be in this *url*
    directory (otherwise, use the `-linkoffline` option).

    _Note:_ The `package-list` and `element-list` files are generated by the
    `javadoc` tool when generating the API documentation and should not be
    modified by the user.

    When you use the `javadoc` tool to document packages, it uses the
    `package-list` file to determine the packages declared in an API. When you
    generate API documents for modules, the `javadoc` tool uses the
    `element-list` file to determine the modules and packages declared in an
    API.

    The `javadoc` tool reads the names from the appropriate list file and then
    links to the packages or modules at that URL.

    When the `javadoc` tool runs, the *url* value is copied into the `<a href>`
    links that are created. Therefore, *url* must be the URL to the directory
    and not to a file.

    You can use an absolute link for *url* to enable your documents to link to
    a document on any web site, or you can use a relative link to link only to
    a relative location. If you use a relative link, then the value you pass in
    should be the relative path from the destination directory (specified with
    the `-d` option) to the directory containing the packages being linked to.
    When you specify an absolute link, you usually use an HTTP link. However,
    if you want to link to a file system that has no web server, then you can
    use a file link. Use a file link only when everyone who wants to access the
    generated documentation shares the same file system. In all cases, and on
    all operating systems, use a slash as the separator, whether the URL is
    absolute or relative, and `https:`, `http:`, or `file:` as specified in the
    [RFC 1738: Uniform Resource Locators (URL)](https://www.rfc-editor.org/info/rfc1738).

    ```
    -link https://<host>/<directory>/<directory>/.../<name>
    -link http://<host>/<directory>/<directory>/.../<name>
    -link file://<host>/<directory>/<directory>/.../<name>
    -link <directory>/<directory>/.../<name>
    ```

<span id="option-link-modularity-mismatch">`--link-modularity-mismatch` (`warn`|`info`)</span>
:   Specifies whether external documentation with wrong modularity (e.g.
    non-modular documentation for a modular library, or the reverse case)
    should be reported as a warning (`warn`) or just a message (`info`).
    The default behavior is to report a warning.

<span id="option-linkoffline">`-linkoffline` *url1* *url2*</span>
:   This option is a variation of the `-link` option. They both create links to
    `javadoc` generated documentation for externally referenced classes. You
    can specify multiple `-linkoffline` options in a specified `javadoc` tool
    run.

    Use the `-linkoffline` option when:

    -   Linking to a document on the web that the `javadoc` tool can't access
        through a web connection

    -   The `package-list` or `element-list` file of the external document
        either isn't accessible or doesn't exist at the URL location, but does
        exist at a different location and can be specified by either the
        `package-list` or `element-list` file (typically local).

    _Note:_ The `package-list` and `element-list` files are generated by the
    `javadoc` tool when generating the API documentation and should not be
    modified by the user.

    If *url1* is accessible only on the World Wide Web, then the `-linkoffline`
    option removes the constraint that the `javadoc` tool must have a web
    connection to generate documentation.

    Another use of the `-linkoffline` option is as a work-around to update
    documents. After you have run the `javadoc` tool on a full set of packages
    or modules, you can run the `javadoc` tool again on a smaller set of
    changed packages or modules, so that the updated files can be inserted back
    into the original set.

    For example, the `-linkoffline` option takes two arguments. The first is
    for the string to be embedded in the `<a href>` links, and the second tells
    the `javadoc` tool where to find either the `package-list` or
    `element-list` file.

    The *url1* or *url2* value is the absolute or relative URL of the directory
    that contains the external `javadoc` generated documentation that you want
    to link to. When relative, the value should be the relative path from the
    destination directory (specified with the `-d` option) to the root of the
    packages being linked to. See *url* in the `-link` option.

<span id="option-link-platform-properties">`--link-platform-properties` *url*</span>
:   Specifies a properties file used to configure links to platform
    documentation.

    The *url* argument is expected to point to a properties file containing
    one or more entries with the following format, where `<version>` is the
    platform version as passed to the `--release` or `--source` option and
    `<url>` is the base URL of the corresponding platform API documentation:

    ```
    doclet.platform.docs.<version>=<url>
    ```

    For instance, a properties file containing URLs for releases 15 to 17 might
    contain the following lines:

    ```
    doclet.platform.docs.15=https://example.com/api/15/
    doclet.platform.docs.16=https://example.com/api/16/
    doclet.platform.docs.17=https://example.com/api/17/
    ```

    If the properties file does not contain an entry for a particular release
    no platform links are generated.

<span id="option-linksource">`-linksource`</span>
:   Creates an HTML version of each source file (with line numbers) and adds
    links to them from the standard HTML documentation. Links are created for
    classes, interfaces, constructors, methods, and fields whose declarations
    are in a source file. Otherwise, links aren't created, such as for default
    constructors and generated classes.

    This option exposes all private implementation details in the included
    source files, including private classes, private fields, and the bodies of
    private methods, regardless of the `-public`, `-package`, `-protected`, and
    `-private` options. Unless you also use the `-private` option, not all
    private classes or interfaces are accessible through links.

    Each link appears on the name of the identifier in its declaration. For
    example, the link to the source code of the `Button` class would be on the
    word `Button`:

    ```
    public class Button extends Component implements Accessible
    ```

    The link to the source code of the `getLabel` method in the `Button` class
    is on the word `getLabel`:

    ```
    public String getLabel()
    ```

<span id="option-main-stylesheet">`--main-stylesheet` *file* or `-stylesheetfile` *file*</span>
:   Specifies the path of an alternate stylesheet file that contains the
    definitions for the CSS styles used in the generated documentation. This
    option lets you override the default. If you do not specify the option, the
    `javadoc` tool will create and use a default stylesheet. The file name can
    be any name and isn't restricted to `stylesheet.css`. The
    `--main-stylesheet` option is the preferred form.

    Command-line example:

    ```
    javadoc --main-stylesheet main_stylesheet.css pkg_foo
    ```

<span id="option-nocomment">`-nocomment`</span>
:   Suppresses the entire comment body, including the main description and all
    tags, and generate only declarations. This option lets you reuse source
    files that were originally intended for a different purpose so that you can
    produce skeleton HTML documentation during the early stages of a new
    project.

<span id="option-nodeprecated">`-nodeprecated`</span>
:   Prevents the generation of any deprecated API in the documentation. This
    does what the `-nodeprecatedlist` option does, and it doesn't generate any
    deprecated API throughout the rest of the documentation. This is useful
    when writing code when you don't want to be distracted by the deprecated
    code.

<span id="option-nodeprecatedlist">`-nodeprecatedlist`</span>
:   Prevents the generation of the file that contains the list of deprecated
    APIs (`deprecated-list.html`) and the link in the navigation bar to that
    page. The `javadoc` tool continues to generate the deprecated API
    throughout the rest of the document. This is useful when your source code
    contains no deprecated APIs, and you want to make the navigation bar
    cleaner.

<span id="option-no-fonts">`--no-fonts`</span>
:    Prevents inclusion of font files in the generated documentation. This can
     be useful if the documentation uses a custom stylesheet which does not
     use the default fonts.

<span id="option-nohelp">`-nohelp`</span>
:   Omits the **HELP** link in the navigation bar at the top of each
    generated page.

<span id="option-noindex">`-noindex`</span>
:   Omits the index from the generated documents. The index is produced by
    default.

<span id="option-nonavbar">`-nonavbar`</span>
:   Prevents the generation of the navigation bar and header. The `-nonavbar`
    option has no effect on the `-bottom` option. The `-nonavbar` option is
    useful when you are interested only in the content and have no need for
    navigation, such as when you are converting the files to PostScript or PDF
    for printing only.

<span id="option-no-platform-links">`--no-platform-links`</span>
:   Prevents the generation of links to platform documentation.
    These links are generated by default.

<span id="option-noqualifier">`-noqualifier` *name1*`,`*name2...*</span>
:   Excludes the list of qualifiers from the output. The package name is
    removed from places where class or interface names appear.
    For historical reasons, `:` can be used anywhere in the argument as a
    separator instead of `,`.

    The following example omits all package qualifiers: `-noqualifier all`.

    The following example omits `java.lang` and `java.io` package qualifiers:
    `-noqualifier java.lang:java.io`.

    The following example omits package qualifiers starting with `java` and
    `com.sun` subpackages, but not `javax: -noqualifier java.*:com.sun.*`.

    Where a package qualifier would appear due to the previous behavior, the
    name can be suitably shortened. This rule is in effect whether or not the
    `-noqualifier` option is used.

<span id="option-nosince">`-nosince`</span>
:   Omits from the generated documentation the `Since` sections derived from
    any `since` tags.

<span id="option-notimestamp">`-notimestamp`</span>
:   Suppresses the time stamp, which is hidden in an HTML comment in the
    generated HTML near the top of each page. The `-notimestamp` option is
    useful when you want to run the `javadoc` tool on two source bases and
    compare them, because it prevents time stamps from causing a difference
    (which would otherwise be a difference on every page). The time stamp
    includes the `javadoc` tool release number.

<span id="option-notree">`-notree`</span>
:   Omits the class and interface hierarchy pages from the generated documents.
    These are the pages you reach using the **TREE** link in the navigation bar.
    The hierarchy is produced by default.

<span id="option-override-methods">`--override-methods` (`detail`|`summary`)</span>
:   Documents overridden methods in the detail or summary sections.
    The default is `detail`.

<span id="option-overview">`-overview` *filename*</span>
:   Specifies that the `javadoc` tool should retrieve the content for the overview
    documentation from the file specified by *filename* and place it on
    the Overview page (`overview-summary.html`). If the *filename* is a relative
    path, it is evaluated relative to the current working directory.

    The file may be an HTML file, with a filename ending in `.html`,
    or a Markdown file, with a filename ending in `.md`.
    If the file is an HTML file, the content for the overview documentation
    is taken from the `<main>` element in the file, if one is present, or from
    the `<body>` element is there is no `<main>` element.  If the file is
    a Markdown file, the entire content of the file is used.

    The title on the overview page is set by `-doctitle`.

    _Note:_ older versions of the `javadoc` tool assumed that any use of this
    option was for an HTML file, and allowed any extension for the *filename*.

<span id="option-serialwarn">`-serialwarn`</span>
:   Reports compile-time warnings for missing `@serial` tags. By default,
    Javadoc reports no serial warnings. Use this option to display the serial
    warnings, which helps to properly document default serializable fields and
    `writeExternal` methods.

<span id="option-since">`--since` *release*(`,`*release*)*</span>
:   Generates documentation for APIs that were added or newly deprecated in the
    specified *release*s.

    If the `@since` tag in the `javadoc` comment of an element in the documented
    source code matches a *release* passed as the option argument, information
    about the element and the release it was added in is included in a "New API"
    page.

    If the "Deprecated API" page is generated and the `since` element of the
    `java.lang.Deprecated` annotation of a documented element matches a *release*
    in the option arguments, information about the release the element was
    deprecated in is added to the "Deprecated API" page.

    Releases are compared using case-sensitive string comparison.

<span id="option-since-label">`--since-label` *text*</span>
:   Specifies the *text* to use in the heading of the "New API" page. This may
    contain information about the releases covered in the page, e.g.
    "New API in release 2.0", or "New API since release 1".

<span id="option-snippet-path">`--snippet-path` *snippetpathlist*</span>
:   Specifies the search paths for finding files for external snippets.
    The *snippetpathlist* can contain multiple paths by separating them with the
    platform path separator (`;` on Windows; `:` on other platforms.)
    The standard doclet first searches the `snippet-files` subdirectory in the
    package containing the snippet, and then searches all the directories in the
    given list.

<span id="option-sourcetab">`-sourcetab` *tab-length*</span>
:   Specifies the number of spaces each tab uses in the source.

<span id="option-spec-base-url">`--spec-base-url` *url*</span>
:   Specifies the base URL for relative URLs in `@spec` tags, to be used when
    generating links to any external specifications. It can either be an
    absolute URL, or a relative URL, in which case it is evaluated relative
    to the base directory of the generated output files. The default value is
    equivalent to `{@docRoot}/../specs`.

<span id="option-splitindex">`-splitindex`</span>
:   Splits the index file into multiple files, alphabetically, one file per
    letter, plus a file for any index entries that start with non-alphabetical
    symbols.

<span id="option-syntax-highlight">`--syntax-highlight`</span>
:   Enables syntax highlighting for code fragments in `{@snippet}` tags and
    `<pre><code>` elements. For snippets, the `lang` attribute is used to
    determine the language of code fragments, which defaults to "java" for
    inline snippets and is derived from the file extension for external
    snippets. In HTML `<pre><code>` tags, the `class` attribute can be used
    to specify the language of the contained code fragment as shown below:

    ```
    <pre><code class="language-java">...</code></pre>
    ```

    If neither of these attributes is available automatic language detection is
    applied. To disable syntax highlighting for a code fragment set the language
    to "text" using one of the mechanisms described above. The languages and
    formats supported by this option are Java, Properties, JSON, HTML and XML.

<span id="option-tag">`-tag` *name*:*locations*:*header*</span>
:   Specifies a custom tag with a single argument. For the `javadoc` tool to
    spell-check tag names, it is important to include a `-tag` option for every
    custom tag that is present in the source code, disabling (with `X`) those
    that aren't being output in the current run. The colon (`:`) is always the
    separator. To include a colon in the tag name, escape it with a backward
    slash (`\`). The `-tag` option outputs the tag heading, *header*, in bold,
    followed on the next line by the text from its single argument. Similar to
    any block tag, the argument text can contain inline tags, which are also
    interpreted. The output is similar to standard one-argument tags, such as
    the `@return` and `@author` tags. Omitting a *header* value causes the
    *name* to be the heading.  *locations* is a list of characters specifying
    the kinds of declarations in which the tag may be used. The following
    characters may be used, in either uppercase or lowercase:

    * `A`: all declarations
    * `C`: constructors
    * `F`: fields
    * `M`: methods
    * `O`: the overview page and other documentation files in `doc-files` subdirectories
    * `P`: packages
    * `S`: modules
    * `T`: types (classes and interfaces)
    * `X`: nowhere: the tag is disabled, and will be ignored

    The order in which tags are given on the command line will be used
    as the order in which the tags appear in the generated output.
    You can include standard tags in the order given on the command line
    by using the `-tag` option with no *locations* or *header*.

<span id="option-taglet">`-taglet` *class*</span>
:   Specifies the fully qualified name of the taglet used in generating the
    documentation for that tag. Use the fully qualified name for the *class*
    value. This taglet also defines the number of text arguments that the
    custom tag has. The taglet accepts those arguments, processes them, and
    generates the output.

    Taglets are useful for block or inline tags. They can have any number of
    arguments and implement custom behavior, such as making text bold,
    formatting bullets, writing out the text to a file, or starting other
    processes. Taglets can only determine where a tag should appear and in what
    form. All other decisions are made by the doclet. A taglet can't do things
    such as remove a class name from the list of included classes. However, it
    can execute side effects, such as printing the tag's text to a file or
    triggering another process. Use the `-tagletpath` option to specify the
    path to the taglet. The following example inserts the To Do taglet after
    Parameters and ahead of Throws in the generated pages.

    ```
    -taglet com.sun.tools.doclets.ToDoTaglet
    -tagletpath /home/taglets
    -tag return
    -tag param
    -tag todo
    -tag throws
    -tag see
    ```

    Alternately, you can use the `-taglet` option in place of its `-tag`
    option, but that might be difficult to read.

<span id="option-tagletpath">`-tagletpath` *tagletpathlist*</span>
:   Specifies the search paths for finding taglet class files.
    The *tagletpathlist* can contain multiple paths by separating them with the
    platform path separator (`;` on Windows; `:` on other platforms.)
    The `javadoc` tool searches all subdirectories of the specified paths.

<span id="option-top">`-top` *html-code*</span>
:   Specifies the text to be placed at the top of each output file.

<span id="option-use">`-use`</span>
:   Creates class and package usage pages. Includes one Use page for each
    documented class and package. The page describes what packages, classes,
    methods, constructors, and fields use any API of the specified class or
    package. Given class C, things that use class C would include subclasses of
    C, fields declared as C, methods that return C, and methods and
    constructors with parameters of type C. For example, you can look at the
    Use page for the `String` type. Because the `getName` method in the
    `java.awt.Font` class returns type `String`, the `getName` method uses
    `String` and so the `getName` method appears on the Use page for `String`.
    This documents only uses of the API, not the implementation. When a method
    uses `String` in its implementation, but doesn't take a string as an
    argument or return a string, that isn't considered a use of `String`. To
    access the generated Use page, go to the class or package and click the
    **USE** link in the navigation bar.

<span id="option-version">`-version`</span>
:   Includes the text of any `version` tags in the generated documentation.
    This text is omitted by default.
    Note: To find out what version of the `javadoc` tool you are using, use
    the `--version` option (with two hyphens).

<span id="option-windowtitle">`-windowtitle` *title*</span>
:   Specifies the title to be placed in the HTML `<title>` tag. The text
    specified in the `title` tag appears in the window title and in any browser
    bookmarks (favorite places) that someone creates for this page. This title
    should not contain any HTML tags because a browser will not interpret them
    correctly. Use escape characters on any internal quotation marks within the
    `title` tag. If the `-windowtitle` option is omitted, then the `javadoc`
    tool uses the value of the `-doctitle` option for the `-windowtitle`
    option. For example, `javadoc -windowtitle "My Library" com.mypackage`.

### Extra Options for the Standard Doclet

The following are additional options provided by the standard doclet and are
subject to change without notice. Additional options are less commonly
used or are otherwise regarded as advanced.

<span id="option-date">`--date` *date-and-time*</span>
:   Specifies the value to be used to timestamp the generated pages, in
    [ISO 8601][] format. The specified value must be within 10 years of the
    current date and time. It is an error to specify both `-notimestamp`
    and `--date`. Using a specific value means the generated documentation
    can be part of a [reproducible build][]. If the option is not given, the
    default value is the current date and  time. For example:

    ```
    javadoc --date 2022-02-01T17:41:59-08:00 mypackage
    ```

<span id="option-legal-notices">`--legal-notices` (`default`|`none`|*directory*)</span>
:   Specifies the location from which to copy legal files to the generated
    documentation. If the option is not specified or is used with the value
    `default`, the files are copied from the default location.
    If the argument is used with value `none`, no files are copied. Every
    other argument is interpreted as directory from which to copy the legal
    files.

<span id="option-no-frames">`--no-frames`</span>
:   This option is no longer supported and reports a warning.

<span id="option-Xdoclint">`-Xdoclint`</span>
:   Enables recommended checks for problems in documentation comments.

    By default, the `-Xdoclint` option is enabled. Disable it with the option
    `-Xdoclint:none`.

    For more details, see [DocLint](#doclint).

<span id="option-Xdoclint-flags">`-Xdoclint:`*flag*,*flag*,...</span>
:   Enables or disables specific checks for different kinds of issues in
    documentation comments.

    Each *flag* can be one of `all`, `none`, or `[-]`*group* where
    *group* has one of the following values:
    `accessibility`, `html`, `missing`, `reference`, `syntax`.
    For more details on these values, see [DocLint Groups](#groups).

    When specifying two or more flags, you can either use a single `-Xdoclint:...`
    option, listing all the desired flags, or you can use multiple options
    giving one or more flag in each option. For example, use either of the
    following commands to check for the HTML, syntax, and accessibility issues
    in the file `MyFile.java`.

    ```
    javadoc -Xdoclint:html -Xdoclint:syntax -Xdoclint:accessibility MyFile.java
    javadoc -Xdoclint:html,syntax,accessibility MyFile.java
    ```

    The following examples illustrate how to change what DocLint reports:

    * `-Xdoclint:none` --- disables all checks
    * `-Xdoclint:`*group* --- enables *group* checks
    * `-Xdoclint:all` --- enables all groups of checks
    * `-Xdoclint:all,-`*group* --- enables all checks except *group* checks

    For more details, see [DocLint](#doclint).

<span id="option-Xdoclint-package">`-Xdoclint/package:`\[`-`\]*packages*</span>
:   Enables or disables checks in specific packages. *packages* is a comma
    separated list of package specifiers. A package specifier is either a
    qualified name of a package or a package name prefix followed by `*`, which
    expands to all subpackages of the given package. Prefix the package
    specifier with `-` to disable checks for the specified packages.

    For more details, see [DocLint](#doclint).

<span id="option-Xdocrootparent">`-Xdocrootparent` *url*</span>
:   Replaces all `@docRoot` items followed by `/..` in documentation comments
    with *url*.

[ISO 8601]: https://www.iso.org/iso-8601-date-and-time-format.html
[reproducible build]: https://reproducible-builds.org/

## DocLint

DocLint provides the ability to check for possible problems in documentation
comments. Problems may be reported as warnings or errors, depending on their
severity. For example, a missing comment may be bad style that deserves a
warning, but a link to an unknown Java declaration is more serious and deserves
an error. Problems are organized into [groups](#groups), and options can be
used to enable or disable messages in one or more groups. Within the source
code, messages in one or more groups can be [suppressed](#suppressing-messages)
by using `@SuppressWarnings` annotations.

When invoked from `javadoc`, by default DocLint checks all comments that are
used in the generated documentation. It thus relies on other command-line
options to determine which declarations, and which corresponding documentation
comments will be included. _Note:_ this may mean that even comments on some
private members of serializable classes will also be checked, if the members
need to be documented in the generated `Serialized Forms` page.

In contrast, when DocLint is invoked from `javac`, DocLint solely relies on the
various `-Xdoclint...` options to determine which documentation comments to
check.

DocLint doesn't attempt to fix invalid input, it just reports it.

_Note:_ DocLint doesn't guarantee the completeness of these checks.
In particular, it isn't a full HTML compliance checker. The goal is to just
report common errors in a convenient manner.

### Groups

The checks performed by DocLint are organized into groups. The warnings and
errors in each group can be enabled or disabled with command-line options, or
suppressed with `@SuppressWarnings` annotations.

The groups are as follows:

* `accessibility` --- Checks for issues related to accessibility.<br>
  For example, no `alt` attribute specified in an `<img>` element,
  or no caption or summary attributes specified in a `<table>` element.

  Issues are reported as errors if a downstream validation tool might
  be expected to report an error in the files generated by `javadoc`.

  For reference, see the [Web Content Accessibility Guidelines][].


* `html` --- Detects common high-level HTML issues.<br>
  For example, putting block elements inside inline elements, or not closing
  elements that require an end tag.

  Issues are reported as errors if a downstream validation tool might
  be expected to report an error in the files generated by `javadoc`.

  For reference, see the [HTML Living Standard][].


* `missing` --- Checks for missing documentation comments or tags.<br>
  For example, a missing comment on a class declaration, or a missing `@param`
  or `@return` tag in the comment for a method declaration.

  Issues related to missing items are typically reported as warnings because
  they are unlikely to be reported as errors by downstream validation tools
  that may be used to check the output generated by `javadoc`.


* `reference` --- Checks for issues relating to the references to Java API
  elements from documentation comment tags.<br>
  For example, the reference in `@see` or `{@link ...}` cannot be found,
  or a bad name is given for `@param` or `@throws`.

  Issues are typically reported as errors because while the issue may not cause
  problems in the generated files, the author has likely made a mistake that
  will lead to incorrect or unexpected documentation.


* `syntax` --- Checks for low-level syntactic issues in documentation comments.<br>
  For example, unescaped angle brackets (`<` and `>`) and ampersands (`&`)
  and invalid documentation comment tags.<br>

  Issues are typically reported as errors because the issues may
  lead to incorrect or unexpected documentation.

[HTML Living Standard]: https://html.spec.whatwg.org/multipage/
[Web Content Accessibility Guidelines]: https://www.w3.org/WAI/standards-guidelines/wcag/


### Suppressing Messages

DocLint checks for and recognizes two strings that may be present in the
arguments for an `@SuppressWarnings` annotation.

* `doclint`
* `doclint:`_LIST_

where _LIST_ is a comma-separated list of one or more of
`accessibility`, `html`, `missing`, `reference`, `syntax`.

The names in _LIST_ are the same [group](#groups) names supported by the
command-line `-Xdoclint` option for `javac` and `javadoc`. (This is the same
convention honored by the `javac` `-Xlint` option and the corresponding names
supported by `@SuppressWarnings`.)

The names in _LIST_ can equivalently be specified in separate arguments of
the annotation. For example, the following are equivalent:

* `@SuppressWarnings("doclint:accessibility,missing")`
* `@SuppressWarnings("doclint:accessibility", "doclint:missing")`

When DocLint detects an issue in a documentation comment, it checks for the
presence of `@SuppressWarnings` on the associated declaration and on all
lexically enclosing declarations. The issue will be ignored if any such
annotation is found containing the simple string `doclint` or the longer form
`doclint:LIST` where _LIST_ contains the name of the group for the issue.

_Note:_ as with other uses of `@SuppressWarnings`, using the annotation on a
module or package declaration only affects that declaration; it does not affect
the contents of the module or package in other source files.

All messages related to an issue are suppressed by the presence of an
appropriate `@SuppressWarnings` annotation: this includes errors as well as
warnings.

_Note:_ It is only possible to *suppress* messages.
If an annotation of `@SuppressWarnings("doclint")` is given on a top-level
declaration, all DocLint messages for that declaration and any enclosed
declarations will be suppressed; it is not possible to selectively re-enable
messages for issues in enclosed declarations.


### Comparison with downstream validation tools

DocLint is a utility built into `javac` and `javadoc` that checks the content
of documentation comments, as found in source files. In contrast, downstream
validation tools can be used to validate the output generated from those
documentation comments by `javadoc` and the standard doclet.

Although there is some overlap in functionality, the two mechanisms are
different and each has its own strengths and weaknesses.

* Downstream validation tools can check the end result of any generated
  documentation, as it will be seen by the end user.
  This includes content from all sources, including documentation comments,
  the standard doclet itself, user-provided taglets, and content supplied
  via command-line options. Because such tools are analyzing complete HTML
  pages, they can do more complete checks than can DocLint.
  However, when a problem is found in the generated pages, it can be harder to
  track down exactly where in the build pipeline the problem needs to be fixed.


* DocLint checks the content of documentation comments, in source files.
  This makes it very easy to identify the exact position of any issues that
  may be found. DocLint can also detect some semantic errors in
  documentation comments that downstream tools cannot detect,
  such as missing comments, using an `@return` tag in a method returning `void`,
  or an `@param` tag describing a non-existent parameter.
  But by its nature, DocLint cannot report on problems such as
  missing links, or errors in user-provided custom taglets, or
  problems in the standard doclet itself. It also cannot reliably
  detect errors in documentation comments at the boundaries
  between content in a documentation comment and content generated
  by a custom taglet.