src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/debugger/MachineDescription.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * version 2 for more details (a copy is included in the LICENSE file that
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package sun.jvm.hotspot.debugger;

import java.io.Serializable;

/** Encapsulates machine-specific information that currently must be
    exported up to the Java level. Implementations must be
    serializable. */

public interface MachineDescription extends Serializable {
  /** Returns the size of an address in bytes. Currently needed to be
      able to traverse arrays of pointers or oops. */
  public long getAddressSize();

  /** Returns the maximum value of the C integer type with the given
      size in bytes and signedness. Throws IllegalArgumentException if
      the size in bytes is not legal for a C type (or can not be
      handled by this system). Note that the current implementation
      does not currently handle unsigned 8-byte longs properly. */
  public long cIntegerTypeMaxValue(long sizeInBytes, boolean isUnsigned);

  /** Returns the minimum value of the C integer type with the given
      size in bytes and signedness. Throws IllegalArgumentException if
      the size in bytes is not legal for a C type (or can not be
      handled by this system). */
  public long cIntegerTypeMinValue(long sizeInBytes, boolean isUnsigned);

  /** Indicates whether the CPU is big- or little-endian. This
      information is typically only needed by the Debugger
      implementation. */
  public boolean isBigEndian();

  /** Indicates whether the underlying machine supports the LP64 data
      model. */
  public boolean isLP64();

  /** Indicates whether the underlying machine supports 64-bit types
      that are only 32-bit aligned. */
  default public boolean supports32bitAlignmentOf64bitTypes() {
    return false;
  }
}