org.objectweb.asm.tree.analysis

Class BasicInterpreter

java.lang.Object

org.objectweb.asm.tree.analysis.Interpreter<BasicValue>

org.objectweb.asm.tree.analysis.BasicInterpreter

All Implemented Interfaces:

org.objectweb.asm.Opcodes

Direct Known Subclasses:

BasicVerifier

public class BasicInterpreter
extends Interpreter<BasicValue>
implements org.objectweb.asm.Opcodes

An Interpreter for BasicValue values.

Field Summary

Fields

Modifier and Type	Field and Description
static org.objectweb.asm.Type	NULL_TYPE Special type used for the null literal.

Fields inherited from class org.objectweb.asm.tree.analysis.Interpreter

api

Fields inherited from interface org.objectweb.asm.Opcodes

AALOAD, AASTORE, ACC_ABSTRACT, ACC_ANNOTATION, ACC_BRIDGE, ACC_DEPRECATED, ACC_ENUM, ACC_FINAL, ACC_INTERFACE, ACC_MANDATED, ACC_MODULE, ACC_NATIVE, ACC_OPEN, ACC_PRIVATE, ACC_PROTECTED, ACC_PUBLIC, ACC_STATIC, ACC_STATIC_PHASE, ACC_STRICT, ACC_SUPER, ACC_SYNCHRONIZED, ACC_SYNTHETIC, ACC_TRANSIENT, ACC_TRANSITIVE, ACC_VARARGS, ACC_VOLATILE, ACONST_NULL, ALOAD, ANEWARRAY, ARETURN, ARRAYLENGTH, ASM4, ASM5, ASM6, ASM7, ASTORE, ATHROW, BALOAD, BASTORE, BIPUSH, CALOAD, CASTORE, CHECKCAST, D2F, D2I, D2L, DADD, DALOAD, DASTORE, DCMPG, DCMPL, DCONST_0, DCONST_1, DDIV, DLOAD, DMUL, DNEG, DOUBLE, DREM, DRETURN, DSTORE, DSUB, DUP, DUP_X1, DUP_X2, DUP2, DUP2_X1, DUP2_X2, F_APPEND, F_CHOP, F_FULL, F_NEW, F_SAME, F_SAME1, F2D, F2I, F2L, FADD, FALOAD, FASTORE, FCMPG, FCMPL, FCONST_0, FCONST_1, FCONST_2, FDIV, FLOAD, FLOAT, FMUL, FNEG, FREM, FRETURN, FSTORE, FSUB, GETFIELD, GETSTATIC, GOTO, H_GETFIELD, H_GETSTATIC, H_INVOKEINTERFACE, H_INVOKESPECIAL, H_INVOKESTATIC, H_INVOKEVIRTUAL, H_NEWINVOKESPECIAL, H_PUTFIELD, H_PUTSTATIC, I2B, I2C, I2D, I2F, I2L, I2S, IADD, IALOAD, IAND, IASTORE, ICONST_0, ICONST_1, ICONST_2, ICONST_3, ICONST_4, ICONST_5, ICONST_M1, IDIV, IF_ACMPEQ, IF_ACMPNE, IF_ICMPEQ, IF_ICMPGE, IF_ICMPGT, IF_ICMPLE, IF_ICMPLT, IF_ICMPNE, IFEQ, IFGE, IFGT, IFLE, IFLT, IFNE, IFNONNULL, IFNULL, IINC, ILOAD, IMUL, INEG, INSTANCEOF, INTEGER, INVOKEDYNAMIC, INVOKEINTERFACE, INVOKESPECIAL, INVOKESTATIC, INVOKEVIRTUAL, IOR, IREM, IRETURN, ISHL, ISHR, ISTORE, ISUB, IUSHR, IXOR, JSR, L2D, L2F, L2I, LADD, LALOAD, LAND, LASTORE, LCMP, LCONST_0, LCONST_1, LDC, LDIV, LLOAD, LMUL, LNEG, LONG, LOOKUPSWITCH, LOR, LREM, LRETURN, LSHL, LSHR, LSTORE, LSUB, LUSHR, LXOR, MONITORENTER, MONITOREXIT, MULTIANEWARRAY, NEW, NEWARRAY, NOP, NULL, POP, POP2, PUTFIELD, PUTSTATIC, RET, RETURN, SALOAD, SASTORE, SIPUSH, SOURCE_DEPRECATED, SOURCE_MASK, SWAP, T_BOOLEAN, T_BYTE, T_CHAR, T_DOUBLE, T_FLOAT, T_INT, T_LONG, T_SHORT, TABLESWITCH, TOP, UNINITIALIZED_THIS, V_PREVIEW, V1_1, V1_2, V1_3, V1_4, V1_5, V1_6, V1_7, V1_8, V10, V11, V12, V13, V14, V9

Constructor Summary

Constructors

Modifier	Constructor and Description
	BasicInterpreter() Constructs a new BasicInterpreter for the latest ASM API version.
protected	BasicInterpreter(int api) Constructs a new BasicInterpreter.

Method Summary

Modifier and Type	Method and Description
BasicValue	binaryOperation(org.objectweb.asm.tree.AbstractInsnNode insn, BasicValue value1, BasicValue value2) Interprets a bytecode instruction with two arguments.
BasicValue	copyOperation(org.objectweb.asm.tree.AbstractInsnNode insn, BasicValue value) Interprets a bytecode instruction that moves a value on the stack or to or from local variables.
BasicValue	merge(BasicValue value1, BasicValue value2) Merges two values.
BasicValue	naryOperation(org.objectweb.asm.tree.AbstractInsnNode insn, java.util.List<? extends BasicValue> values) Interprets a bytecode instruction with a variable number of arguments.
BasicValue	newOperation(org.objectweb.asm.tree.AbstractInsnNode insn) Interprets a bytecode instruction without arguments.
BasicValue	newValue(org.objectweb.asm.Type type) Creates a new value that represents the given type.
void	returnOperation(org.objectweb.asm.tree.AbstractInsnNode insn, BasicValue value, BasicValue expected) Interprets a bytecode return instruction.
BasicValue	ternaryOperation(org.objectweb.asm.tree.AbstractInsnNode insn, BasicValue value1, BasicValue value2, BasicValue value3) Interprets a bytecode instruction with three arguments.
BasicValue	unaryOperation(org.objectweb.asm.tree.AbstractInsnNode insn, BasicValue value) Interprets a bytecode instruction with a single argument.

Methods inherited from class org.objectweb.asm.tree.analysis.Interpreter

newEmptyValue, newExceptionValue, newParameterValue, newReturnTypeValue

Methods inherited from class java.lang.Object

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

Field Detail

NULL_TYPE

public static final org.objectweb.asm.Type NULL_TYPE

Special type used for the null literal. This is an object reference type with descriptor 'Lnull;'.

Constructor Detail

BasicInterpreter

public BasicInterpreter()

Constructs a new BasicInterpreter for the latest ASM API version. Subclasses must not use this constructor. Instead, they must use the BasicInterpreter(int) version.

BasicInterpreter

protected BasicInterpreter(int api)

Constructs a new BasicInterpreter.

Parameters:

api - the ASM API version supported by this interpreter. Must be one of Opcodes.ASM4, Opcodes.ASM5, Opcodes.ASM6 or Opcodes.ASM7.

Method Detail

newValue

public BasicValue newValue(org.objectweb.asm.Type type)

Description copied from class: Interpreter

Creates a new value that represents the given type.

Called for method parameters (including this), exception handler variable and with null type for variables reserved by long and double types.

An interpreter may choose to implement one or more of Interpreter.newReturnTypeValue(Type), Interpreter.newParameterValue(boolean, int, Type), Interpreter.newEmptyValue(int), Interpreter.newExceptionValue(TryCatchBlockNode, Frame, Type) to distinguish different types of new value.

Specified by:

newValue in class Interpreter<BasicValue>

Parameters:

type - a primitive or reference type, or null to represent an uninitialized value.

Returns:

a value that represents the given type. The size of the returned value must be equal to the size of the given type.

newOperation

public BasicValue newOperation(org.objectweb.asm.tree.AbstractInsnNode insn)
                        throws AnalyzerException

Description copied from class: Interpreter

Interprets a bytecode instruction without arguments. This method is called for the following opcodes:

ACONST_NULL, ICONST_M1, ICONST_0, ICONST_1, ICONST_2, ICONST_3, ICONST_4, ICONST_5, LCONST_0, LCONST_1, FCONST_0, FCONST_1, FCONST_2, DCONST_0, DCONST_1, BIPUSH, SIPUSH, LDC, JSR, GETSTATIC, NEW

Specified by:

newOperation in class Interpreter<BasicValue>

Parameters:

insn - the bytecode instruction to be interpreted.

Returns:

the result of the interpretation of the given instruction.

Throws:

AnalyzerException - if an error occurred during the interpretation.

copyOperation

public BasicValue copyOperation(org.objectweb.asm.tree.AbstractInsnNode insn,
                                BasicValue value)
                         throws AnalyzerException

Description copied from class: Interpreter

Interprets a bytecode instruction that moves a value on the stack or to or from local variables. This method is called for the following opcodes:

ILOAD, LLOAD, FLOAD, DLOAD, ALOAD, ISTORE, LSTORE, FSTORE, DSTORE, ASTORE, DUP, DUP_X1, DUP_X2, DUP2, DUP2_X1, DUP2_X2, SWAP

Specified by:

copyOperation in class Interpreter<BasicValue>

Parameters:

insn - the bytecode instruction to be interpreted.

value - the value that must be moved by the instruction.

Returns:

the result of the interpretation of the given instruction. The returned value must be equal to the given value.

Throws:

AnalyzerException - if an error occurred during the interpretation.

unaryOperation

public BasicValue unaryOperation(org.objectweb.asm.tree.AbstractInsnNode insn,
                                 BasicValue value)
                          throws AnalyzerException

Description copied from class: Interpreter

Interprets a bytecode instruction with a single argument. This method is called for the following opcodes:

INEG, LNEG, FNEG, DNEG, IINC, I2L, I2F, I2D, L2I, L2F, L2D, F2I, F2L, F2D, D2I, D2L, D2F, I2B, I2C, I2S, IFEQ, IFNE, IFLT, IFGE, IFGT, IFLE, TABLESWITCH, LOOKUPSWITCH, IRETURN, LRETURN, FRETURN, DRETURN, ARETURN, PUTSTATIC, GETFIELD, NEWARRAY, ANEWARRAY, ARRAYLENGTH, ATHROW, CHECKCAST, INSTANCEOF, MONITORENTER, MONITOREXIT, IFNULL, IFNONNULL

Specified by:

unaryOperation in class Interpreter<BasicValue>

Parameters:

insn - the bytecode instruction to be interpreted.

value - the argument of the instruction to be interpreted.

Returns:

the result of the interpretation of the given instruction.

Throws:

AnalyzerException - if an error occurred during the interpretation.

binaryOperation

public BasicValue binaryOperation(org.objectweb.asm.tree.AbstractInsnNode insn,
                                  BasicValue value1,
                                  BasicValue value2)
                           throws AnalyzerException

Description copied from class: Interpreter

Interprets a bytecode instruction with two arguments. This method is called for the following opcodes:

IALOAD, LALOAD, FALOAD, DALOAD, AALOAD, BALOAD, CALOAD, SALOAD, IADD, LADD, FADD, DADD, ISUB, LSUB, FSUB, DSUB, IMUL, LMUL, FMUL, DMUL, IDIV, LDIV, FDIV, DDIV, IREM, LREM, FREM, DREM, ISHL, LSHL, ISHR, LSHR, IUSHR, LUSHR, IAND, LAND, IOR, LOR, IXOR, LXOR, LCMP, FCMPL, FCMPG, DCMPL, DCMPG, IF_ICMPEQ, IF_ICMPNE, IF_ICMPLT, IF_ICMPGE, IF_ICMPGT, IF_ICMPLE, IF_ACMPEQ, IF_ACMPNE, PUTFIELD

Specified by:

binaryOperation in class Interpreter<BasicValue>

Parameters:

insn - the bytecode instruction to be interpreted.

value1 - the first argument of the instruction to be interpreted.

value2 - the second argument of the instruction to be interpreted.

Returns:

the result of the interpretation of the given instruction.

Throws:

AnalyzerException - if an error occurred during the interpretation.

ternaryOperation

public BasicValue ternaryOperation(org.objectweb.asm.tree.AbstractInsnNode insn,
                                   BasicValue value1,
                                   BasicValue value2,
                                   BasicValue value3)
                            throws AnalyzerException

Description copied from class: Interpreter

Interprets a bytecode instruction with three arguments. This method is called for the following opcodes:

IASTORE, LASTORE, FASTORE, DASTORE, AASTORE, BASTORE, CASTORE, SASTORE

Specified by:

ternaryOperation in class Interpreter<BasicValue>

Parameters:

insn - the bytecode instruction to be interpreted.

value1 - the first argument of the instruction to be interpreted.

value2 - the second argument of the instruction to be interpreted.

value3 - the third argument of the instruction to be interpreted.

Returns:

the result of the interpretation of the given instruction.

Throws:

AnalyzerException - if an error occurred during the interpretation.

naryOperation

public BasicValue naryOperation(org.objectweb.asm.tree.AbstractInsnNode insn,
                                java.util.List<? extends BasicValue> values)
                         throws AnalyzerException

Description copied from class: Interpreter

Interprets a bytecode instruction with a variable number of arguments. This method is called for the following opcodes:

INVOKEVIRTUAL, INVOKESPECIAL, INVOKESTATIC, INVOKEINTERFACE, MULTIANEWARRAY and INVOKEDYNAMIC

Specified by:

naryOperation in class Interpreter<BasicValue>

Parameters:

insn - the bytecode instruction to be interpreted.

values - the arguments of the instruction to be interpreted.

Returns:

the result of the interpretation of the given instruction.

Throws:

AnalyzerException - if an error occurred during the interpretation.

returnOperation

public void returnOperation(org.objectweb.asm.tree.AbstractInsnNode insn,
                            BasicValue value,
                            BasicValue expected)
                     throws AnalyzerException

Description copied from class: Interpreter

Interprets a bytecode return instruction. This method is called for the following opcodes:

IRETURN, LRETURN, FRETURN, DRETURN, ARETURN

Specified by:

returnOperation in class Interpreter<BasicValue>

Parameters:

insn - the bytecode instruction to be interpreted.

value - the argument of the instruction to be interpreted.

expected - the expected return type of the analyzed method.

Throws:

AnalyzerException - if an error occurred during the interpretation.

merge

public BasicValue merge(BasicValue value1,
                        BasicValue value2)

Description copied from class: Interpreter

Merges two values. The merge operation must return a value that represents both values (for instance, if the two values are two types, the merged value must be a common super type of the two types. If the two values are integer intervals, the merged value must be an interval that contains the previous ones. Likewise for other types of values).

Specified by:

merge in class Interpreter<BasicValue>

Parameters:

value1 - a value.

value2 - another value.

Returns:

the merged value. If the merged value is equal to value1, this method must return value1.