Module java.base

Package java.io

Class ObjectStreamField

java.lang.Object

java.io.ObjectStreamField

All Implemented Interfaces:

Comparable<Object>

public class ObjectStreamField
extends Object
implements Comparable<Object>

A description of a Serializable field from a Serializable class. An array of ObjectStreamFields is used to declare the Serializable fields of a class.

Since:

1.2

See Also:

• ObjectStreamClass

Constructor Summary

Constructors

Constructor	Description
ObjectStreamField(String name, Class<?> type)	Create a Serializable field with the specified type.
ObjectStreamField(String name, Class<?> type, boolean unshared)	Creates an ObjectStreamField representing a serializable field with the given name and type.

Method Summary

Modifier and Type	Method	Description
int	compareTo(Object obj)	Compare this field with another ObjectStreamField.
String	getName()	Get the name of this field.
int	getOffset()	Offset of field within instance data.
Class<?>	getType()	Get the type of the field.
char	getTypeCode()	Returns character encoding of field type.
String	getTypeString()	Return the JVM type signature.
boolean	isPrimitive()	Return true if this field has a primitive type.
boolean	isUnshared()	Returns boolean value indicating whether or not the serializable field represented by this ObjectStreamField instance is unshared.
protected void	setOffset(int offset)	Offset within instance data.
String	toString()	Return a string that describes this field.

Methods declared in class java.lang.Object

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

Constructor Details

ObjectStreamField

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

Create a Serializable field with the specified type. This field should be documented with a serialField tag.

Parameters:

name - the name of the serializable field

type - the Class object of the serializable field

ObjectStreamField

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

Creates an ObjectStreamField representing a serializable field with the given name and type. If unshared is false, values of the represented field are serialized and deserialized in the default manner--if the field is non-primitive, object values are serialized and deserialized as if they had been written and read by calls to writeObject and readObject. If unshared is true, values of the represented field are serialized and deserialized as if they had been written and read by calls to writeUnshared and readUnshared.

Parameters:

name - field name

type - field type

unshared - if false, write/read field values in the same manner as writeObject/readObject; if true, write/read in the same manner as writeUnshared/readUnshared

Since:

1.4

Method Details

getName

public String getName()

Get the name of this field.

Returns:

a String representing the name of the serializable field

getType

public Class<?> getType()

Get the type of the field. If the type is non-primitive and this ObjectStreamField was obtained from a deserialized ObjectStreamClass instance, then Object.class is returned. Otherwise, the Class object for the type of the field is returned.

Returns:

a Class object representing the type of the serializable field

getTypeCode

public char getTypeCode()

Returns character encoding of field type. The encoding is as follows:

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

Returns:

the typecode of the serializable field

getTypeString

public String getTypeString()

Return the JVM type signature.

Returns:

null if this field has a primitive type.

getOffset

public int getOffset()

Offset of field within instance data.

Returns:

the offset of this field

See Also:

• setOffset(int)

setOffset

protected void setOffset(int offset)

Offset within instance data.

Parameters:

offset - the offset of the field

See Also:

• getOffset()

isPrimitive

public boolean isPrimitive()

Return true if this field has a primitive type.

Returns:

true if and only if this field corresponds to a primitive type

isUnshared

public boolean isUnshared()

Returns boolean value indicating whether or not the serializable field represented by this ObjectStreamField instance is unshared.

Returns:

true if this field is unshared

Since:

1.4

compareTo

public int compareTo(Object obj)

Compare this field with another ObjectStreamField. Return -1 if this is smaller, 0 if equal, 1 if greater. Types that are primitives are "smaller" than object types. If equal, the field names are compared.

Specified by:

compareTo in interface Comparable<Object>

Parameters:

obj - the object to be compared.

Returns:

a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object.

toString

public String toString()

Return a string that describes this field.

Overrides:

toString in class Object

Returns:

a string representation of the object