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## com.ibm.dtfj.java
Interface JavaObject

    public interface JavaObject

Represents a Java object

Author:
  pburka

Method Summary
`void` | `arraycopy(int srcStart, java.lang.Object dst, int dstStart, int length)` Copies data from the image array into a local Java array.
`boolean` | `equals(java.lang.Object obj)`
`int` | `getArraySize()` Get the number of elements in this array.
`long` | `getHashcode()` Fetch the basic hash code for the object.
`ImagePointer` | `getID()` The ID of an object is a unique address is memory which identifies the object.
`JavaClass` | `getJavaClass()` Get the JavaClass instance which represents the class of this object.
`long` | `getPersistentHashcode()` Fetch the basic hash code of the object in the image.
`java.util.Iterator` | `getReferences()` Get the set of references from this object.
`java.util.Iterator` | `getSections()` An object is represented in the Java runtime by one or more regions of memory.
`long` | `getSize()` Get the number of bytes of memory occupied by this object.
`int` | `hashCode()`
`boolean` | `isArray()` Is this object an array ?

Method Detail

### getJavaClass

    JavaClass getJavaClass()
                           throws CorruptDataException

  Get the JavaClass instance which represents the class of this object.

  Returns:
    the JavaClass instance which represents the class of this object
  Throws:
    `CorruptDataException`

### isArray

    boolean isArray()
                    throws CorruptDataException

  Is this object an array ?

  Returns:
    true if the receiver represents an instance of an array, or false otherwise
  Throws:
    `CorruptDataException`

### getArraySize

    int getArraySize()
                     throws CorruptDataException

  Get the number of elements in this array.

  Returns:
    the number of elements in this array

  Throws:
    `CorruptDataException`
    `java.lang.IllegalArgumentException` - if the receiver is not an array

### arraycopy

    void arraycopy(int srcStart,
                   java.lang.Object dst,
                   int dstStart,
                   int length)
                   throws CorruptDataException,
                          MemoryAccessException

  Copies data from the image array into a local Java array. The dst object must be an array of the appropriate type -- a base type array for base types, or a JavaObject array for reference arrays.

  Parameters:
    `srcStart` - index in the receiver to start copying from
    `dst` - the destination array
    `dstStart` - index in dst to start copying into
    `length` - the number of elements to be copied
  Throws:
    `CorruptDataException`
    `MemoryAccessException`
    `java.lang.IllegalArgumentException` - if the receiver is not an array, or if dst is not an array of the appropriate type
    `java.lang.IndexOutOfBoundsException` - if srcStart, dstStart, or length are out of bounds in either the receiver or dst

### getSize

    long getSize()
                 throws CorruptDataException

  Get the number of bytes of memory occupied by this object.

  Returns:
    the number of bytes of memory occupied by this object. The memory may not necessarily be contiguous
  Throws:
    `CorruptDataException`

### getHashcode

    long getHashcode()
                     throws DataUnavailable,
                            CorruptDataException

  Fetch the basic hash code for the object. This is the hash code which would be returned if a Java thread had requested it. Typically the hash code is based on the address of an object, and may change if the object is moved by a garbage collect cycle.

  Returns:
    the basic hash code of the object in the image.
  Throws:
    `DataUnavailable` - if the hash code cannot be determined
    `CorruptDataException`
  See Also:
    `getPersistentHashcode()`

### getPersistentHashcode

    long getPersistentHashcode()
                               throws DataUnavailable,
                                      CorruptDataException

  Fetch the basic hash code of the object in the image. This hash code is guaranteed to be persistent between multiple snapshots of the same Image. If the hash code cannot be determined, or if the hash code for this object could change between snapshots, an exception is thrown.

  If the VM uses a 'hasBeenHashed' bit, the value of this bit can be inferred by calling getPersistentHashcode(). If the persistent hash code is not available, then the 'hasBeenHashed' bit has not been set, and the hash of the object could change if the object moves between snapshots

  Returns:
    the basic hash code of the object in the image
  Throws:
    `DataUnavailable` - if a hash code cannot be determined, or if the hash code could change between successive snapshots
    `CorruptDataException`
  See Also:
    `getHashcode()`

### getID

    ImagePointer getID()

  The ID of an object is a unique address is memory which identifies the object. The data at this memory is implementation defined. The object may be non-contiguous. Portions of the object may appear below or above this address.

  Returns:
    the runtime-wide unique identifier for the object

### getSections

    java.util.Iterator getSections()

  An object is represented in the Java runtime by one or more regions of memory. These include the object's header and the data in the object. In certain allocation strategies, an object's header and data may be allocated contiguously. In this case, this method may return an iterator for a single section. In other schemes, the header may be separate from the data or the data may be broken up into multiple regions. Additionally, this function does not guarantee that the memory used by this object is not also shared by one or more other objects. Callers should not make any assumptions about the contents of the memory.

  Returns:
    a collection of sections that make up this object
  See Also:
    `ImageSection`, `CorruptData`

### getReferences

    java.util.Iterator getReferences()

  Get the set of references from this object.

  Returns:
    an iterator of JavaReferences
  See Also:
    `JavaReference`, `CorruptData`

### equals

    boolean equals(java.lang.Object obj)

  Overrides:
    `equals` in class `java.lang.Object`
  Parameters:
    `obj` -
  Returns:
    True obj refers to the same Java Object in the image

### hashCode

    int hashCode()

  Overrides:
    `hashCode` in class `java.lang.Object`

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