| /* |
| * Copyright (c) 2004, 2018 Oracle and/or its affiliates. All rights reserved. |
| * Copyright (c) 1999 The Apache Software Foundation. All rights |
| * Copyright (c) 1999 The Apache Software Foundation. All rights |
| * reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * 3. The end-user documentation included with the redistribution, if |
| * any, must include the following acknowlegement: |
| * "This product includes software developed by the |
| * Apache Software Foundation (http://www.apache.org/)." |
| * Alternately, this acknowlegement may appear in the software itself, |
| * if and wherever such third-party acknowlegements normally appear. |
| * |
| * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software |
| * Foundation" must not be used to endorse or promote products derived |
| * from this software without prior written permission. For written |
| * permission, please contact apache@apache.org. |
| * |
| * 5. Products derived from this software may not be called "Apache" |
| * nor may "Apache" appear in their names without prior written |
| * permission of the Apache Group. |
| * |
| * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED |
| * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR |
| * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF |
| * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
| * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| * ==================================================================== |
| * |
| * This software consists of voluntary contributions made by many |
| * individuals on behalf of the Apache Software Foundation. For more |
| * information on the Apache Software Foundation, please see |
| * <http://www.apache.org/>. |
| */ |
| |
| package demo.taglib; |
| |
| import org.apache.taglibs.standard.lang.support.ExpressionEvaluatorManager; |
| |
| import jakarta.servlet.jsp.JspException; |
| import jakarta.servlet.jsp.JspTagException; |
| import jakarta.servlet.jsp.tagext.BodyTagSupport; |
| |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.InputStreamReader; |
| import java.io.OutputStream; |
| import java.io.OutputStreamWriter; |
| import java.io.Reader; |
| import java.io.StringReader; |
| import java.io.Writer; |
| |
| /** |
| * <p>Tag handler for <escapeHtml> |
| * |
| * @author Pierre Delisle |
| * @version $Revision: 1.3 $ $Date: 2004/11/14 07:33:18 $ |
| */ |
| public class EscapeHtmlTag extends BodyTagSupport { |
| |
| //********************************************************************* |
| // Instance variables |
| |
| private String reader; |
| private String writer; |
| |
| //********************************************************************* |
| // Constructors |
| |
| public EscapeHtmlTag() { |
| super(); |
| init(); |
| } |
| |
| |
| private void init() { |
| reader = null; |
| writer = null; |
| } |
| |
| |
| //********************************************************************* |
| // Tag's properties |
| |
| /** |
| * Tag's 'reader' attribute |
| */ |
| public void setReader(String reader) { |
| this.reader = reader; |
| } |
| |
| |
| /** |
| * Tag's 'writer' attribute |
| */ |
| public void setWriter(String reader) { |
| this.writer = writer; |
| } |
| |
| //********************************************************************* |
| // TagSupport methods |
| |
| public int doEndTag() throws JspException { |
| Reader in; |
| Writer out; |
| |
| if (reader == null) { |
| String bcs = getBodyContent().getString().trim(); |
| if (bcs == null || bcs.equals("")) { |
| throw new JspTagException("In <escapeHtml>, 'reader' " + |
| "not specified and no non-whitespace content inside the tag."); |
| } |
| in = castToReader(bcs); |
| } else { |
| in = castToReader(eval("reader", reader, Object.class)); |
| } |
| |
| if (writer == null) { |
| out = pageContext.getOut(); |
| } else { |
| out = castToWriter(eval("writer", writer, Object.class)); |
| } |
| |
| transform(in, out); |
| return EVAL_PAGE; |
| } |
| |
| |
| /** |
| * Releases any resources we may have (or inherit) |
| */ |
| public void release() { |
| super.release(); |
| init(); |
| } |
| |
| //********************************************************************* |
| // Tag's scific behavior methods |
| |
| /** |
| * Transform |
| */ |
| public void transform(Reader reader, Writer writer) |
| throws JspException { |
| int c; |
| try { |
| writer.write("<pre>"); |
| while ((c = reader.read()) != -1) { |
| if (c == '<') { |
| writer.write("<"); |
| } else if (c == '>') { |
| writer.write(">"); |
| } else { |
| writer.write(c); |
| } |
| } |
| writer.write("</pre>"); |
| } catch (IOException ex) { |
| throw new JspException("EscapeHtml: " + |
| "error copying chars", ex); |
| } |
| } |
| |
| //********************************************************************* |
| // Utility methods |
| |
| /** |
| * Evaluate elexprvalue |
| */ |
| private Object eval(String attName, String attValue, Class clazz) |
| throws JspException { |
| Object obj = ExpressionEvaluatorManager.evaluate(attName, attValue, |
| clazz, this, |
| pageContext); |
| if (obj == null) { |
| throw new JspException("escapeHtml"); |
| } else { |
| return obj; |
| } |
| } |
| |
| |
| public static Reader castToReader(Object obj) throws JspException { |
| if (obj instanceof InputStream) { |
| return new InputStreamReader((InputStream) obj); |
| } else if (obj instanceof Reader) { |
| return (Reader) obj; |
| } else if (obj instanceof String) { |
| return new StringReader((String) obj); |
| } |
| throw new JspException("Invalid type '" + obj.getClass().getName() + |
| "' for castToReader()"); |
| } |
| |
| |
| public static Writer castToWriter(Object obj) throws JspException { |
| if (obj instanceof OutputStream) { |
| return new OutputStreamWriter((OutputStream) obj); |
| } else if (obj instanceof Writer) { |
| return (Writer) obj; |
| /*@@@ |
| } else if (obj instanceof String) { |
| return new StringWriter(); |
| */ |
| } |
| throw new JspException("Invalid type '" + obj.getClass().getName() + |
| "' for castToWriter()"); |
| } |
| |
| } |