gnu.bytecode
Class Type

java.lang.Object
  gnu.bytecode.Type

Direct Known Subclasses:

ObjectType, PrimType

public abstract class Type
extends java.lang.Object

Field Summary

static ClassType	boolean_ctype
static PrimType	boolean_type
static Method	booleanValue_method
static PrimType	byte_type
static PrimType	char_type
static PrimType	double_type
static Method	doubleValue_method
static PrimType	float_type
static Method	floatValue_method
static PrimType	int_type
static Method	intValue_method
static ClassType	java_lang_Class_type
static PrimType	long_type
static Method	longValue_method
static PrimType	neverReturnsType The "return type" of an expression that never returns, such as a throw.
static ObjectType	nullType The magic type of null.
static ClassType	number_type
static ClassType	pointer_type
protected java.lang.Class	reflectClass
static PrimType	short_type
static ClassType	string_type
static ClassType	throwable_type
static Method	toString_method
static ClassType	tostring_type
static Type[]	typeArray0
static PrimType	void_type

Constructor Summary

protected

Type()

Method Summary

abstract java.lang.Object	coerceFromObject(java.lang.Object obj) Convert an object to a value of this Type.
java.lang.Object	coerceToObject(java.lang.Object obj)
abstract int	compare(Type other) Return a numeric code showing "subtype" relationship: 1: if other is a pure subtype of this; 0: if has the same values; -1: if this is a pure subtype of other; -2: if they have values in common but neither is a subtype of the other; -3: if the types have no values in common.
void	emitCoerceFromObject(CodeAttr code) Compile code to coerce/convert from Object to this type.
void	emitCoerceToObject(CodeAttr code) Compile code to convert a object of this type on the stack to Object.
void	emitIsInstance(CodeAttr code)
Type	getImplementationType() The type used to implement types not natively understood by the JVM.
java.lang.String	getName()
java.lang.Class	getReflectClass() Get the java.lang.Class object for the representation type.
java.lang.String	getSignature()
int	getSize()
static Type	getType(java.lang.String name) Find an Type with the given name, or create a new one.
int	hashCode()
boolean	isInstance(java.lang.Object obj)
static boolean	isMoreSpecific(Type[] t1, Type[] t2) Return true iff t1[i].isSubtype(t2[i]) for all i.
boolean	isSubtype(Type other) Return true if this is a "subtype" of other.
static boolean	isValidJavaTypeName(java.lang.String name)
boolean	isVoid()
static Type	lookupType(java.lang.String name)
static Type	lowestCommonSuperType(Type t1, Type t2) Computes the common supertype Interfaces are not taken into account.
static Type	make(java.lang.Class reflectClass)
Type	promote()
static void	registerTypeForClass(java.lang.Class clas, Type type) Register that the Type for class is type.
protected void	setName(java.lang.String name)
void	setReflectClass(java.lang.Class rclass)
protected void	setSignature(java.lang.String sig)
static int	signatureLength(java.lang.String sig)
static int	signatureLength(java.lang.String sig, int pos) Return the length of the signature starting at a given string position.
static java.lang.String	signatureToName(java.lang.String sig) Returns the Java-level type name from a given signature.
static PrimType	signatureToPrimitive(char sig) Returns the primitive type corresponding to a signature character.
static Type	signatureToType(java.lang.String sig) Get a Type corresponding to the given signature string.
static Type	signatureToType(java.lang.String sig, int off, int len) Get a Type corresponding to the given signature string.
protected static int	swappedCompareResult(int code) Change result from compare to compensate for argument swapping.
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

byte_type

public static final PrimType byte_type

short_type

public static final PrimType short_type

int_type

public static final PrimType int_type

long_type

public static final PrimType long_type

float_type

public static final PrimType float_type

double_type

public static final PrimType double_type

boolean_type

public static final PrimType boolean_type

char_type

public static final PrimType char_type

void_type

public static final PrimType void_type

neverReturnsType

public static final PrimType neverReturnsType

The "return type" of an expression that never returns, such as a throw.

nullType

public static final ObjectType nullType

The magic type of null.

string_type

public static ClassType string_type

tostring_type

public static final ClassType tostring_type

pointer_type

public static final ClassType pointer_type

boolean_ctype

public static final ClassType boolean_ctype

throwable_type

public static final ClassType throwable_type

typeArray0

public static final Type[] typeArray0

toString_method

public static final Method toString_method

number_type

public static final ClassType number_type

intValue_method

public static final Method intValue_method

longValue_method

public static final Method longValue_method

floatValue_method

public static final Method floatValue_method

doubleValue_method

public static final Method doubleValue_method

booleanValue_method

public static final Method booleanValue_method

java_lang_Class_type

public static final ClassType java_lang_Class_type

reflectClass

protected java.lang.Class reflectClass

Constructor Detail

Type

protected Type()

Method Detail

getImplementationType

public Type getImplementationType()

The type used to implement types not natively understood by the JVM. Usually, the identity function. However, a language might handle union types or template types or type expressions calculated at run time. In that case return the type used at the JVM level, and known at compile time.

lookupType

public static Type lookupType(java.lang.String name)

getType

public static Type getType(java.lang.String name)

Find an Type with the given name, or create a new one. Use this for "library classes", where you need the field/method types, but not one where you are about to generate code for.

Parameters:

name - the name of the class (e..g. "java.lang.String").

registerTypeForClass

public static void registerTypeForClass(java.lang.Class clas,
                                        Type type)

Register that the Type for class is type.

make

public static Type make(java.lang.Class reflectClass)

getSignature

public final java.lang.String getSignature()

setSignature

protected void setSignature(java.lang.String sig)

promote

public Type promote()

getSize

public final int getSize()

isVoid

public final boolean isVoid()

signatureToPrimitive

public static PrimType signatureToPrimitive(char sig)

Returns the primitive type corresponding to a signature character.

Returns:

a primitive type, or null if there is no such type.

signatureToType

public static Type signatureToType(java.lang.String sig,
                                   int off,
                                   int len)

Get a Type corresponding to the given signature string.

signatureToType

public static Type signatureToType(java.lang.String sig)

Get a Type corresponding to the given signature string.

signatureLength

public static int signatureLength(java.lang.String sig,
                                  int pos)

Return the length of the signature starting at a given string position. Returns -1 for an invalid signature.

signatureLength

public static int signatureLength(java.lang.String sig)

signatureToName

public static java.lang.String signatureToName(java.lang.String sig)

Returns the Java-level type name from a given signature. Returns null for an invalid signature.

getName

public final java.lang.String getName()

setName

protected void setName(java.lang.String name)

isValidJavaTypeName

public static boolean isValidJavaTypeName(java.lang.String name)

isInstance

public boolean isInstance(java.lang.Object obj)

isSubtype

public final boolean isSubtype(Type other)

Return true if this is a "subtype" of other.

lowestCommonSuperType

public static Type lowestCommonSuperType(Type t1,
                                         Type t2)

Computes the common supertype Interfaces are not taken into account. This would be difficult, since interfaces allow multiple-inheritance. This means that there may exists multiple common supertypes to t1 and t2 that are not comparable.

Returns:

the lowest type that is both above t1 and t2, or null if t1 and t2 have no common supertype.

compare

public abstract int compare(Type other)

Return a numeric code showing "subtype" relationship: 1: if other is a pure subtype of this; 0: if has the same values; -1: if this is a pure subtype of other; -2: if they have values in common but neither is a subtype of the other; -3: if the types have no values in common. "Same member" is rather loose; by "A is a subtype of B" we mean that all instance of A can be "widened" to B. More formally, A.compare(B) returns: 1: all B values can be converted to A without a coercion failure (i.e. a ClassCastException or overflow or major loss of information), but not vice versa. 0: all A values can be converted to B without a coercion failure and vice versa; -1: all A values can be converted to B without a coercion failure not not vice versa; -2: there are (potentially) some A values that can be converted to B, and some B values can be converted to A; -3: there are no A values that can be converted to B, and neither are there any B values that can be converted to A.

swappedCompareResult

protected static int swappedCompareResult(int code)

Change result from compare to compensate for argument swapping.

isMoreSpecific

public static boolean isMoreSpecific(Type[] t1,
                                     Type[] t2)

Return true iff t1[i].isSubtype(t2[i]) for all i.

emitIsInstance

public void emitIsInstance(CodeAttr code)

coerceFromObject

public abstract java.lang.Object coerceFromObject(java.lang.Object obj)

Convert an object to a value of this Type. Throw a ClassCastException when this is not possible.

coerceToObject

public java.lang.Object coerceToObject(java.lang.Object obj)

emitCoerceToObject

public void emitCoerceToObject(CodeAttr code)

Compile code to convert a object of this type on the stack to Object.

emitCoerceFromObject

public void emitCoerceFromObject(CodeAttr code)

Compile code to coerce/convert from Object to this type.

getReflectClass

public java.lang.Class getReflectClass()

Get the java.lang.Class object for the representation type.

setReflectClass

public void setReflectClass(java.lang.Class rclass)

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object