Class BytecodeHelper

  • All Implemented Interfaces:
    org.objectweb.asm.Opcodes

    public class BytecodeHelper
    extends Object
    implements org.objectweb.asm.Opcodes
    A helper class for bytecode generation with AsmClassGenerator.
    • Field Summary

      • 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_RECORD, 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, ASM10_EXPERIMENTAL, ASM4, ASM5, ASM6, ASM7, ASM8, ASM9, 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, V15, V16, V17, V18, V9
    • Constructor Summary

      Constructors 
      Constructor Description
      BytecodeHelper()  
    • Constructor Detail

      • BytecodeHelper

        public BytecodeHelper()
    • Method Detail

      • getClassInternalName

        public static String getClassInternalName​(ClassNode t)
        Returns:
        the ASM internal name of the type
      • getClassInternalName

        public static String getClassInternalName​(Class t)
        Returns:
        the ASM internal name of the type
      • getClassInternalName

        public static String getClassInternalName​(String name)
        Returns:
        the ASM internal name of the type
      • getMethodDescriptor

        public static String getMethodDescriptor​(MethodNode methodNode)
        Returns a method descriptor for the given MethodNode.
        Parameters:
        methodNode - the method node for which to create the descriptor
        Returns:
        a method descriptor as defined in section JVMS section 4.3.3
      • getMethodDescriptor

        public static String getMethodDescriptor​(ClassNode returnType,
                                                 Parameter[] parameters)
        Returns:
        the ASM method type descriptor
      • getMethodDescriptor

        public static String getMethodDescriptor​(ClassNode returnType,
                                                 ClassNode[] parameterTypes)
        Returns:
        the ASM method type descriptor
      • getMethodDescriptor

        public static String getMethodDescriptor​(Class returnType,
                                                 Class[] paramTypes)
        Returns:
        the ASM method type descriptor
      • getClassLoadingTypeDescription

        public static String getClassLoadingTypeDescription​(ClassNode c)
        array types are special: eg.: String[]: classname: [Ljava.lang.String; Object: classname: java.lang.Object int[] : classname: [I unlike getTypeDescription '.' is not replaced by '/'. it seems that makes problems for the class loading if '.' is replaced by '/'
        Returns:
        the ASM type description for class loading
      • getTypeDescription

        public static String getTypeDescription​(Class c)
      • getTypeDescription

        public static String getTypeDescription​(ClassNode c)
        array types are special: eg.: String[]: classname: [Ljava/lang/String; int[]: [I
        Returns:
        the ASM type description
      • getClassInternalNames

        public static String[] getClassInternalNames​(ClassNode[] names)
        Returns:
        an array of ASM internal names of the type
      • pushConstant

        public static void pushConstant​(org.objectweb.asm.MethodVisitor mv,
                                        int value)
      • negateBoolean

        public static void negateBoolean​(org.objectweb.asm.MethodVisitor mv)
        Negate a boolean on stack.
      • formatNameForClassLoading

        public static String formatNameForClassLoading​(String name)
        returns a name that Class.forName() can take. Notably for arrays: [I, [Ljava.lang.String; etc Regular object type: java.lang.String
      • getGenericsMethodSignature

        public static String getGenericsMethodSignature​(MethodNode node)
      • getGenericsSignature

        public static String getGenericsSignature​(ClassNode node)
      • getGenericsBounds

        public static String getGenericsBounds​(ClassNode type)
      • doCast

        public static void doCast​(org.objectweb.asm.MethodVisitor mv,
                                  ClassNode type)
      • doCastToPrimitive

        public static void doCastToPrimitive​(org.objectweb.asm.MethodVisitor mv,
                                             ClassNode sourceType,
                                             ClassNode targetType)
        Given a wrapped number type (Byte, Integer, Short, ...), generates bytecode to convert it to a primitive number (int, long, double) using calls to wrapped.[targetType]Value()
        Parameters:
        mv - method visitor
        sourceType - the wrapped number type
        targetType - the primitive target type
      • doCastToWrappedType

        public static void doCastToWrappedType​(org.objectweb.asm.MethodVisitor mv,
                                               ClassNode sourceType,
                                               ClassNode targetType)
        Given a primitive number type (byte, integer, short, ...), generates bytecode to convert it to a wrapped number (Integer, Long, Double) using calls to [WrappedType].valueOf
        Parameters:
        mv - method visitor
        sourceType - the primitive number type
        targetType - the wrapped target type
      • doCast

        public static void doCast​(org.objectweb.asm.MethodVisitor mv,
                                  Class type)
      • box

        @Deprecated
        public static boolean box​(org.objectweb.asm.MethodVisitor mv,
                                  ClassNode type)
        Deprecated.
        Generates the bytecode to autobox the current value on the stack.
      • box

        @Deprecated
        public static boolean box​(org.objectweb.asm.MethodVisitor mv,
                                  Class type)
        Deprecated.
        Generates the bytecode to autobox the current value on the stack.
      • unbox

        public static void unbox​(org.objectweb.asm.MethodVisitor mv,
                                 ClassNode type)
        Generates the bytecode to unbox the current value on the stack.
      • unbox

        public static void unbox​(org.objectweb.asm.MethodVisitor mv,
                                 Class type)
        Generates the bytecode to unbox the current value on the stack.
      • visitClassLiteral

        public static void visitClassLiteral​(org.objectweb.asm.MethodVisitor mv,
                                             ClassNode classNode)
        Visits a class literal. If the type of the classnode is a primitive type, the generated bytecode will be a GETSTATIC Integer.TYPE. If the classnode is not a primitive type, we will generate a LDC instruction.
      • isClassLiteralPossible

        public static boolean isClassLiteralPossible​(ClassNode classNode)
        Tells if a class node is candidate for class literal bytecode optimization. If so, bytecode may use LDC instructions instead of static constant Class fields to retrieve class literals.
        Parameters:
        classNode - the classnode for which we want to know if bytecode optimization is possible
        Returns:
        true if the bytecode can be optimized
      • isSameCompilationUnit

        public static boolean isSameCompilationUnit​(ClassNode a,
                                                    ClassNode b)
        Returns true if the two classes share the same compilation unit.
        Parameters:
        a - class a
        b - class b
        Returns:
        true if both classes share the same compilation unit
      • hashCode

        public static int hashCode​(String str)
        Computes a hash code for a string. The purpose of this hashcode is to be constant independently of the JDK being used.
        Parameters:
        str - the string for which to compute the hashcode
        Returns:
        hashcode of the string
      • convertPrimitiveToBoolean

        public static void convertPrimitiveToBoolean​(org.objectweb.asm.MethodVisitor mv,
                                                     ClassNode type)
        Converts a primitive type to boolean.
        Parameters:
        mv - method visitor
        type - primitive type to convert
      • doReturn

        public static void doReturn​(org.objectweb.asm.MethodVisitor mv,
                                    ClassNode type)
      • load

        public static void load​(org.objectweb.asm.MethodVisitor mv,
                                ClassNode type,
                                int idx)
      • store

        public static void store​(org.objectweb.asm.MethodVisitor mv,
                                 ClassNode type,
                                 int idx)