Package java.io

Class ObjectStreamField

java.lang.Object

java.io.ObjectStreamField

All Implemented Interfaces:

Comparable<Object>

public class ObjectStreamField
extends Object
implements Comparable<Object>

Describes a field for the purpose of serialization. Classes can define the collection of fields that are serialized, which may be different from the set of all declared fields.

See Also:

ObjectOutputStream.writeFields(), ObjectInputStream.readFields()

Constructor Summary

Constructors

Constructor	Description
ObjectStreamField(String name, Class<?> cl)	Constructs an ObjectStreamField with the specified name and type.
ObjectStreamField(String name, Class<?> cl, boolean unshared)	Constructs an ObjectStreamField with the specified name, type and the indication if it is unshared.

Method Summary

Modifier and Type	Method	Description
int	compareTo(Object o)	Compares this field descriptor to the specified one.
String	getName()	Gets the name of this field.
int	getOffset()	Gets the offset of this field in the object.
Class<?>	getType()	Gets the type of this field.
char	getTypeCode()	Gets a character code for the type of this field.
String	getTypeString()	Gets the type signature used by the VM to represent the type of this field.
boolean	isPrimitive()	Indicates whether this field's type is a primitive type.
boolean	isUnshared()	Indicates whether this field is unshared.
protected void	setOffset(int newValue)	Sets this field's offset in the object.
String	toString()	Returns a string containing a concise, human-readable description of this field descriptor.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

ObjectStreamField

public ObjectStreamField(String name,
                         Class<?> cl)

Constructs an ObjectStreamField with the specified name and type.

Parameters:

name - the name of the field.

cl - the type of the field.

Throws:

NullPointerException - if name or cl is null.

ObjectStreamField

public ObjectStreamField(String name,
                         Class<?> cl,
                         boolean unshared)

Constructs an ObjectStreamField with the specified name, type and the indication if it is unshared.

Parameters:

name - the name of the field.

cl - the type of the field.

unshared - true if the field is written and read unshared; false otherwise.

Throws:

NullPointerException - if name or cl is null.

See Also:

ObjectOutputStream.writeUnshared(Object)

Method Detail

compareTo

public int compareTo(Object o)

Compares this field descriptor to the specified one. Checks first if one of the compared fields has a primitive type and the other one not. If so, the field with the primitive type is considered to be "smaller". If both fields are equal, their names are compared.

Specified by:

compareTo in interface Comparable<Object>

Parameters:

o - the object to compare with.

Returns:

-1 if this field is "smaller" than field o, 0 if both fields are equal; 1 if this field is "greater" than field o.

getName

public String getName()

Gets the name of this field.

Returns:

the field's name.

getOffset

public int getOffset()

Gets the offset of this field in the object.

Returns:

this field's offset.

getType

public Class<?> getType()

Gets the type of this field.

Returns:

a Class object representing the type of the field.

getTypeCode

public char getTypeCode()

Gets a character code for the type of this field. The following codes are used:

 B     byte
 C     char
 D     double
 F     float
 I     int
 J     long
 L     class or interface
 S     short
 Z     boolean
 [     array
 

Returns:

the field's type code.

getTypeString

public String getTypeString()

Gets the type signature used by the VM to represent the type of this field.

Returns:

the signature of this field's class or null if this field's type is primitive.

isPrimitive

public boolean isPrimitive()

Indicates whether this field's type is a primitive type.

Returns:

true if this field's type is primitive; false if the type of this field is a regular class.

setOffset

protected void setOffset(int newValue)

Sets this field's offset in the object.

Parameters:

newValue - the field's new offset.

toString

public String toString()

Returns a string containing a concise, human-readable description of this field descriptor.

Overrides:

toString in class Object

Returns:

a printable representation of this descriptor.

isUnshared

public boolean isUnshared()

Indicates whether this field is unshared.

Returns:

true if this field is unshared, false otherwise.