Top Description Inners Fields Constructors Methods
com.thoughtworks.xstream.core.util

public Class ObjectIdDictionary

extends Object
Class Inheritance
Imports
java.lang.ref.ReferenceQueue, .WeakReference, java.util.HashMap, .Map

Store IDs against given object references.

Behaves similar to java.util.IdentityHashMap, but in JDK1.3 as well. Additionally the implementation keeps track of orphaned IDs by using a WeakReference to store the reference object.

Nested and Inner Type Summary

Modifier and TypeClass and Description
private static class
private class
private static interface

Field Summary

Modifier and TypeField and Description
private final Map<K, V>
private final ReferenceQueue<T>

Constructor Summary

AccessConstructor and Description
public

Method Summary

Modifier and TypeMethod and Description
public void
private void
public boolean
public Object
public void
public int
size()

Inherited from java.lang.Object:
cloneequalsfinalizegetClasshashCodenotifynotifyAlltoStringwaitwaitwait

Field Detail

mapback to summary
private final Map<K, V> map
queueback to summary
private final ReferenceQueue<T> queue

Constructor Detail

ObjectIdDictionaryback to summary
public ObjectIdDictionary()

Method Detail

associateIdback to summary
public void associateId(Object obj, Object id)
cleanupback to summary
private void cleanup()
containsIdback to summary
public boolean containsId(Object item)
lookupIdback to summary
public Object lookupId(Object obj)
removeIdback to summary
public void removeId(Object item)
sizeback to summary
public int size()
com.thoughtworks.xstream.core.util back to summary

private Class ObjectIdDictionary.IdWrapper

extends Object
implements Wrapper
Class Inheritance
  • java.lang.Object
  • com.thoughtworks.xstream.core.util.ObjectIdDictionary.IdWrapper
All Implemented Interfaces
com.thoughtworks.xstream.core.util.ObjectIdDictionary.Wrapper

Field Summary

Modifier and TypeField and Description
private final int
private final Object

Constructor Summary

AccessConstructor and Description
public

Method Summary

Modifier and TypeMethod and Description
public boolean
equals(Object
the reference object with which to compare.
other
)

Overrides java.lang.Object.equals.

Implements com.thoughtworks.xstream.core.util.ObjectIdDictionary.Wrapper.equals.

Indicates whether some other object is "equal to" this one.
public Object
public int
hashCode()

Overrides java.lang.Object.hashCode.

Implements com.thoughtworks.xstream.core.util.ObjectIdDictionary.Wrapper.hashCode.

Returns a hash code value for the object.
public String
toString()

Overrides java.lang.Object.toString.

Implements com.thoughtworks.xstream.core.util.ObjectIdDictionary.Wrapper.toString.

Returns a string representation of the object.
Inherited from java.lang.Object:
clonefinalizegetClassnotifynotifyAllwaitwaitwait

Field Detail

hashCodeback to summary
private final int hashCode
objback to summary
private final Object obj

Constructor Detail

IdWrapperback to summary
public IdWrapper(Object obj)

Method Detail

equalsback to summary
public boolean equals(Object other)

Overrides java.lang.Object.equals.

Implements com.thoughtworks.xstream.core.util.ObjectIdDictionary.Wrapper.equals.

Doc from java.lang.Object.equals.

Indicates whether some other object is "equal to" this one.

The equals method implements an equivalence relation on non-null object references:

  • It is reflexive: for any non-null reference value x, x.equals(x) should return true.
  • It is symmetric: for any non-null reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true.
  • It is transitive: for any non-null reference values x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
  • It is consistent: for any non-null reference values x and y, multiple invocations of x.equals(y) consistently return true or consistently return false, provided no information used in equals comparisons on the objects is modified.
  • For any non-null reference value x, x.equals(null) should return false.

An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes.

Parameters
other:Object

the reference object with which to compare.

Returns:boolean

true if this object is the same as the obj argument; false otherwise.

getback to summary
public Object get()

Implements com.thoughtworks.xstream.core.util.ObjectIdDictionary.Wrapper.get.

hashCodeback to summary
public int hashCode()

Overrides java.lang.Object.hashCode.

Implements com.thoughtworks.xstream.core.util.ObjectIdDictionary.Wrapper.hashCode.

Doc from java.lang.Object.hashCode.

Returns a hash code value for the object. This method is supported for the benefit of hash tables such as those provided by java.util.HashMap.

The general contract of hashCode is:

  • Whenever it is invoked on the same object more than once during an execution of a Java application, the hashCode method must consistently return the same integer, provided no information used in equals comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application.
  • If two objects are equal according to the equals method, then calling the hashCode method on each of the two objects must produce the same integer result.
  • It is not required that if two objects are unequal according to the equals method, then calling the hashCode method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.
Returns:int

a hash code value for this object.

toStringback to summary
public String toString()

Overrides java.lang.Object.toString.

Implements com.thoughtworks.xstream.core.util.ObjectIdDictionary.Wrapper.toString.

Doc from java.lang.Object.toString.

Returns a string representation of the object.

Returns:String

a string representation of the object.

com.thoughtworks.xstream.core.util back to summary

private Class ObjectIdDictionary.WeakIdWrapper

extends WeakReference
implements Wrapper
Class Inheritance
All Implemented Interfaces
com.thoughtworks.xstream.core.util.ObjectIdDictionary.Wrapper

Field Summary

Modifier and TypeField and Description
private final int

Constructor Summary

AccessConstructor and Description
public

Method Summary

Modifier and TypeMethod and Description
public boolean
equals(Object
the reference object with which to compare.
other
)

Overrides java.lang.Object.equals.

Implements com.thoughtworks.xstream.core.util.ObjectIdDictionary.Wrapper.equals.

Indicates whether some other object is "equal to" this one.
public int
hashCode()

Overrides java.lang.Object.hashCode.

Implements com.thoughtworks.xstream.core.util.ObjectIdDictionary.Wrapper.hashCode.

Returns a hash code value for the object.
public String
toString()

Overrides java.lang.Object.toString.

Implements com.thoughtworks.xstream.core.util.ObjectIdDictionary.Wrapper.toString.

Returns a string representation of the object.

Field Detail

hashCodeback to summary
private final int hashCode

Constructor Detail

WeakIdWrapperback to summary
public WeakIdWrapper(Object obj)

Method Detail

equalsback to summary
public boolean equals(Object other)

Overrides java.lang.Object.equals.

Implements com.thoughtworks.xstream.core.util.ObjectIdDictionary.Wrapper.equals.

Doc from java.lang.Object.equals.

Indicates whether some other object is "equal to" this one.

The equals method implements an equivalence relation on non-null object references:

  • It is reflexive: for any non-null reference value x, x.equals(x) should return true.
  • It is symmetric: for any non-null reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true.
  • It is transitive: for any non-null reference values x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
  • It is consistent: for any non-null reference values x and y, multiple invocations of x.equals(y) consistently return true or consistently return false, provided no information used in equals comparisons on the objects is modified.
  • For any non-null reference value x, x.equals(null) should return false.

An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes.

Parameters
other:Object

the reference object with which to compare.

Returns:boolean

true if this object is the same as the obj argument; false otherwise.

hashCodeback to summary
public int hashCode()

Overrides java.lang.Object.hashCode.

Implements com.thoughtworks.xstream.core.util.ObjectIdDictionary.Wrapper.hashCode.

Doc from java.lang.Object.hashCode.

Returns a hash code value for the object. This method is supported for the benefit of hash tables such as those provided by java.util.HashMap.

The general contract of hashCode is:

  • Whenever it is invoked on the same object more than once during an execution of a Java application, the hashCode method must consistently return the same integer, provided no information used in equals comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application.
  • If two objects are equal according to the equals method, then calling the hashCode method on each of the two objects must produce the same integer result.
  • It is not required that if two objects are unequal according to the equals method, then calling the hashCode method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.
Returns:int

a hash code value for this object.

toStringback to summary
public String toString()

Overrides java.lang.Object.toString.

Implements com.thoughtworks.xstream.core.util.ObjectIdDictionary.Wrapper.toString.

Doc from java.lang.Object.toString.

Returns a string representation of the object.

Returns:String

a string representation of the object.

com.thoughtworks.xstream.core.util back to summary

private Interface ObjectIdDictionary.Wrapper

Known Direct Implementers
com.thoughtworks.xstream.core.util.ObjectIdDictionary.IdWrapper, com.thoughtworks.xstream.core.util.ObjectIdDictionary.WeakIdWrapper

Method Summary

Modifier and TypeMethod and Description
public boolean
public Object
get()

public int
public String

Method Detail

equalsback to summary
public boolean equals(Object obj)
getback to summary
public Object get()
hashCodeback to summary
public int hashCode()
toStringback to summary
public String toString()