Class ReferenceType

java.lang.Object

org.apache.bcel.generic.Type

org.apache.bcel.generic.ReferenceType

Direct Known Subclasses:

ArrayType, ObjectType, UninitializedObjectType

public abstract class ReferenceType
extends Type

Superclass for object and array types.

Field Summary

Fields inherited from class Type

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

Modifier and Type	Field	Description
static final BasicType	BOOLEAN	Predefined constant for boolean type.
static final BasicType	BYTE	Predefined constant for byte type.
static final BasicType	CHAR	Predefined constant for char type.
static final ObjectType	CLASS	Predefined constant for Class type.
static final BasicType	DOUBLE	Predefined constant for double type.
static final BasicType	FLOAT	Predefined constant for float type.
static final BasicType	INT	Predefined constant for int type.
static final BasicType	LONG	Predefined constant for long type.
static final Type[]	NO_ARGS	Empty array.
static final ReferenceType	NULL	Predefined constant for null type.
static final ObjectType	OBJECT	Predefined constant for Object type.
static final BasicType	SHORT	Predefined constant for short type.
protected String	signature	Deprecated. (since 6.0) will be made private; do not access directly, use getter/setter
static final ObjectType	STRING	Predefined constant for String type.
static final ObjectType	STRINGBUFFER	Predefined constant for StringBuffer type.
static final ObjectType	THROWABLE	Predefined constant for Throwable type.
protected byte	type	Deprecated. (since 6.0) will be made private; do not access directly, use getter/setter
static final Type	UNKNOWN	Predefined constant for unknown type.
static final BasicType	VOID	Predefined constants

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	ReferenceType(byte t, String s)	Constructs a ReferenceType.

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)	Gets the first common superclass (narrowest ReferenceType referencing a class, not an interface).
boolean	isAssignmentCompatibleWith(Type t)	Tests whether this type is assignment compatible with another type t as defined in the JVM specification; see the AASTORE definition there.
boolean	isCastableTo(Type t)	Tests whether this type is castable to another type t as defined in the JVM specification.

Methods inherited from class Type

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

Modifier and Type	Method	Description
boolean	equals(Object o)
static Type[]	getArgumentTypes(String signature)	Gets the argument types of a method from its signature as an array of Type objects.
String	getClassName()	Gets the class name.
static String	getMethodSignature(Type returnType, Type[] argTypes)	Gets the Java method signature for the given types, for example, int[] f(java.lang.String x) becomes (Ljava/lang/String;)[I.
static Type	getReturnType(String signature)	Gets the return type of a method from its signature as a Type object.
String	getSignature()	Gets the signature for this type.
static String	getSignature(Method meth)	Gets the signature for a method.
int	getSize()	Gets the stack size of this type.
byte	getType()	Gets the type as defined in Constants.
static Type	getType(Class<?> cls)	Gets the BCEL Type object corresponding to a runtime Class.
static Type	getType(String signature)	Gets the Type object corresponding to a signature.
static Type[]	getTypes(Class<?>[] classes)	Gets the BCEL Type objects corresponding to an array of runtime classes.
int	hashCode()	Gets the hash code of this Type.
Type	normalizeForStackOrLocal()	boolean, short and char variable are considered as int in the stack or local variable area.
String	toString()

Methods inherited from class Object

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

Constructor Details

ReferenceType

protected ReferenceType(byte t,
 String s)

Constructs a ReferenceType.

Parameters:

t - The type.

s - The signature.

Method Details

firstCommonSuperclass

@Deprecated
public ReferenceType firstCommonSuperclass(ReferenceType t)
                                    throws 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 NULL, then t is returned. If t is 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".

Parameters:

t - The other type.

Returns:

The first common superclass.

Throws:

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

getFirstCommonSuperclass

public ReferenceType getFirstCommonSuperclass(ReferenceType t)
                                       throws ClassNotFoundException

Gets 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 NULL, then t is returned. If t is 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 superclass 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".

Parameters:

t - The other type.

Returns:

The first common superclass.

Throws:

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

isAssignmentCompatibleWith

public boolean isAssignmentCompatibleWith(Type t)
                                   throws ClassNotFoundException

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

Parameters:

t - The other type.

Returns:

true iff this is assignment compatible with another type t.

Throws:

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

isCastableTo

public boolean isCastableTo(Type t)
                     throws ClassNotFoundException

Tests whether 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 for example CHECKCAST doesn't throw a ClassCastException when casting a null reference to any Object, true is returned in this case.

Parameters:

t - The other type.

Returns:

true iff this type is castable to another type t.

Throws:

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