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.