javolution.io

Class Union

java.lang.Object

javolution.io.Struct

javolution.io.Union

public abstract class Union
extends Struct

Equivalent to C/C++ union; this class works in the same way as Struct (sub-class) except that all members are mapped to the same location in memory.

Here is an example of C union:

 union Number {
     int   asInt;
     float asFloat;
     char  asString[12];
 };

And its Java equivalent:

 public class Number extends Union {
     Signed32   asInt    = new Signed32();
     Float32    asFloat  = new Float32();
     Utf8String asString = new Utf8String(12);
 }

As for any Struct, fields are directly accessible:

  Number num = new Number();
  num.asInt.set(23);
  num.asString.set("23"); // Null terminated (C compatible)
  float f = num.asFloat.get();

Version:

1.0, October 4, 2004

Author:

Jean-Marie Dautelle

Nested Class Summary

Nested classes/interfaces inherited from class javolution.io.Struct

Struct.BitField, Struct.Bool, Struct.Enum16<T extends Enum<T>>, Struct.Enum32<T extends Enum<T>>, Struct.Enum64<T extends Enum<T>>, Struct.Enum8<T extends Enum<T>>, Struct.Float32, Struct.Float64, Struct.Member, Struct.Reference32<S extends Struct>, Struct.Reference64<S extends Struct>, Struct.Signed16, Struct.Signed32, Struct.Signed64, Struct.Signed8, Struct.Unsigned16, Struct.Unsigned32, Struct.Unsigned8, Struct.UTF8String

Field Summary

Fields inherited from class javolution.io.Struct

MAXIMUM_ALIGNMENT

Constructor Summary

Constructors

Constructor and Description
Union() Default constructor.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	isUnion() Returns true.

Methods inherited from class javolution.io.Struct

address, array, array, array, array, array, array, array, byteOrder, getByteBuffer, getByteBufferPosition, inner, isPacked, outer, read, readBits, setByteBuffer, setByteBufferPosition, size, toString, write, writeBits

Methods inherited from class java.lang.Object

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

Constructor Detail

Union

public Union()

Default constructor.

Method Detail

isUnion

public final boolean isUnion()

Returns true.

Overrides:

isUnion in class Struct

Returns:

true

See Also:

Union