Package org.apache.bcel.generic

Class ReferenceType

java.lang.Object

org.apache.bcel.generic.Type

org.apache.bcel.generic.ReferenceType

All Implemented Interfaces:

java.io.Serializable

Direct Known Subclasses:

ArrayType, ObjectType, UninitializedObjectType

public abstract class ReferenceType
extends Type

Super class for object and array types.

Version:

$Id: ReferenceType.java 386056 2006-03-15 11:31:56Z tcurdt $

Author:

M. Dahm

See Also:

Serialized Form

Field Summary

Fields inherited from class org.apache.bcel.generic.Type

BOOLEAN, BYTE, CHAR, CLASS, DOUBLE, FLOAT, INT, LONG, NO_ARGS, NULL, OBJECT, SHORT, signature, STRING, STRINGBUFFER, THROWABLE, type, UNKNOWN, VOID

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	ReferenceType(byte t, java.lang.String s)

Method Summary

Modifier and Type	Method	Description
ReferenceType	firstCommonSuperclass(ReferenceType t)	Deprecated. use getFirstCommonSuperclass(ReferenceType t) which has slightly changed semantics.
ReferenceType	getFirstCommonSuperclass(ReferenceType t)	This commutative operation returns the first common superclass (narrowest ReferenceType referencing a class, not an interface).
boolean	isAssignmentCompatibleWith(Type t)	Return true iff this is assignment compatible with another type t as defined in the JVM specification; see the AASTORE definition there.
boolean	isCastableTo(Type t)	Return true iff this type is castable to another type t as defined in the JVM specification.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from class org.apache.bcel.generic.Type

equals, getArgumentTypes, getMethodSignature, getReturnType, getSignature, getSignature, getSize, getType, getType, getType, getTypes, hashCode, toString

Constructor Detail

ReferenceType

protected ReferenceType(byte t,
                        java.lang.String s)

Method Detail

isCastableTo

public boolean isCastableTo(Type t)
                     throws java.lang.ClassNotFoundException

Return true iff this type is castable to another type t as defined in the JVM specification. The case where this is Type.NULL is not defined (see the CHECKCAST definition in the JVM specification). However, because e.g. CHECKCAST doesn't throw a ClassCastException when casting a null reference to any Object, true is returned in this case.

Throws:

java.lang.ClassNotFoundException - if any classes or interfaces required to determine assignment compatibility can't be found

isAssignmentCompatibleWith

public boolean isAssignmentCompatibleWith(Type t)
                                   throws java.lang.ClassNotFoundException

Return true iff this is assignment compatible with another type t as defined in the JVM specification; see the AASTORE definition there.

Throws:

java.lang.ClassNotFoundException - if any classes or interfaces required to determine assignment compatibility can't be found

getFirstCommonSuperclass

public ReferenceType getFirstCommonSuperclass(ReferenceType t)
                                       throws java.lang.ClassNotFoundException

This commutative operation returns the first common superclass (narrowest ReferenceType referencing a class, not an interface). If one of the types is a superclass of the other, the former is returned. If "this" is Type.NULL, then t is returned. If t is Type.NULL, then "this" is returned. If "this" equals t ['this.equals(t)'] "this" is returned. If "this" or t is an ArrayType, then Type.OBJECT is returned; unless their dimensions match. Then an ArrayType of the same number of dimensions is returned, with its basic type being the first common super class of the basic types of "this" and t. If "this" or t is a ReferenceType referencing an interface, then Type.OBJECT is returned. If not all of the two classes' superclasses cannot be found, "null" is returned. See the JVM specification edition 2, "§4.9.2 The Bytecode Verifier".

Throws:

java.lang.ClassNotFoundException - on failure to find superclasses of this type, or the type passed as a parameter

firstCommonSuperclass

public ReferenceType firstCommonSuperclass(ReferenceType t)
                                    throws java.lang.ClassNotFoundException

Deprecated.

use getFirstCommonSuperclass(ReferenceType t) which has slightly changed semantics.

This commutative operation returns the first common superclass (narrowest ReferenceType referencing a class, not an interface). If one of the types is a superclass of the other, the former is returned. If "this" is Type.NULL, then t is returned. If t is Type.NULL, then "this" is returned. If "this" equals t ['this.equals(t)'] "this" is returned. If "this" or t is an ArrayType, then Type.OBJECT is returned. If "this" or t is a ReferenceType referencing an interface, then Type.OBJECT is returned. If not all of the two classes' superclasses cannot be found, "null" is returned. See the JVM specification edition 2, "§4.9.2 The Bytecode Verifier".

Throws:

java.lang.ClassNotFoundException - on failure to find superclasses of this type, or the type passed as a parameter