Class ASMifier


  • public class ASMifier
    extends Printer
    A Printer that prints the ASM code to generate the classes if visits.
    Author:
    Eric Bruneton
    • Field Detail

      • name

        protected final java.lang.String name
        The name of the visitor variable in the produced code.
      • id

        protected final int id
        Identifier of the annotation visitor variable in the produced code.
      • labelNames

        protected java.util.Map<Label,​java.lang.String> labelNames
        The label names. This map associates String values to Label keys. It is used only in ASMifierMethodVisitor.
    • Constructor Detail

      • ASMifier

        public ASMifier()
        Constructs a new ASMifier. Subclasses must not use this constructor. Instead, they must use the ASMifier(int, String, int) version.
        Throws:
        java.lang.IllegalStateException - If a subclass calls this constructor.
      • ASMifier

        protected ASMifier​(int api,
                           java.lang.String name,
                           int id)
        Constructs a new ASMifier.
        Parameters:
        api - the ASM API version implemented by this class. Must be one of Opcodes.ASM4 or Opcodes.ASM5.
        name - the name of the visitor variable in the produced code.
        id - identifier of the annotation visitor variable in the produced code.
    • Method Detail

      • main

        public static void main​(java.lang.String[] args)
                         throws java.lang.Exception
        Prints the ASM source code to generate the given class to the standard output.

        Usage: ASMifier [-debug] <binary class name or class file name>

        Parameters:
        args - the command line arguments.
        Throws:
        java.lang.Exception - if the class cannot be found, or if an IO exception occurs.
      • visit

        public void visit​(int version,
                          int access,
                          java.lang.String name,
                          java.lang.String signature,
                          java.lang.String superName,
                          java.lang.String[] interfaces)
        Description copied from class: Printer
        Specified by:
        visit in class Printer
        Parameters:
        version - the class version.
        access - the class's access flags (see Opcodes). This parameter also indicates if the class is deprecated.
        name - the internal name of the class (see getInternalName).
        signature - the signature of this class. May be null if the class is not a generic one, and does not extend or implement generic classes or interfaces.
        superName - the internal of name of the super class (see getInternalName). For interfaces, the super class is Object. May be null, but only for the Object class.
        interfaces - the internal names of the class's interfaces (see getInternalName). May be null.
      • visitSource

        public void visitSource​(java.lang.String file,
                                java.lang.String debug)
        Description copied from class: Printer
        Specified by:
        visitSource in class Printer
        Parameters:
        file - the name of the source file from which the class was compiled. May be null.
        debug - additional debug information to compute the correspondance between source and compiled elements of the class. May be null.
      • visitOuterClass

        public void visitOuterClass​(java.lang.String owner,
                                    java.lang.String name,
                                    java.lang.String desc)
        Description copied from class: Printer
        Class outer class. See ClassVisitor.visitOuterClass(java.lang.String, java.lang.String, java.lang.String). Visits the enclosing class of the class. This method must be called only if the class has an enclosing class.
        Specified by:
        visitOuterClass in class Printer
        Parameters:
        owner - internal name of the enclosing class of the class.
        name - the name of the method that contains the class, or null if the class is not enclosed in a method of its enclosing class.
        desc - the descriptor of the method that contains the class, or null if the class is not enclosed in a method of its enclosing class.
      • visitInnerClass

        public void visitInnerClass​(java.lang.String name,
                                    java.lang.String outerName,
                                    java.lang.String innerName,
                                    int access)
        Description copied from class: Printer
        Specified by:
        visitInnerClass in class Printer
        Parameters:
        name - the internal name of an inner class (see getInternalName).
        outerName - the internal name of the class to which the inner class belongs (see getInternalName). May be null for not member classes.
        innerName - the (simple) name of the inner class inside its enclosing class. May be null for anonymous inner classes.
        access - the access flags of the inner class as originally declared in the enclosing class.
      • visitField

        public ASMifier visitField​(int access,
                                   java.lang.String name,
                                   java.lang.String desc,
                                   java.lang.String signature,
                                   java.lang.Object value)
        Description copied from class: Printer
        Specified by:
        visitField in class Printer
        Parameters:
        access - the field's access flags (see Opcodes). This parameter also indicates if the field is synthetic and/or deprecated.
        name - the field's name.
        desc - the field's descriptor (see Type).
        signature - the field's signature. May be null if the field's type does not use generic types.
        value - the field's initial value. This parameter, which may be null if the field does not have an initial value, must be an Integer, a Float, a Long, a Double or a String (for int, float, long or String fields respectively). This parameter is only used for static fields. Its value is ignored for non static fields, which must be initialized through bytecode instructions in constructors or methods.
        Returns:
        the printer
      • visitMethod

        public ASMifier visitMethod​(int access,
                                    java.lang.String name,
                                    java.lang.String desc,
                                    java.lang.String signature,
                                    java.lang.String[] exceptions)
        Description copied from class: Printer
        Specified by:
        visitMethod in class Printer
        Parameters:
        access - the method's access flags (see Opcodes). This parameter also indicates if the method is synthetic and/or deprecated.
        name - the method's name.
        desc - the method's descriptor (see Type).
        signature - the method's signature. May be null if the method parameters, return type and exceptions do not use generic types.
        exceptions - the internal names of the method's exception classes (see getInternalName). May be null.
        Returns:
        the printer
      • visit

        public void visit​(java.lang.String name,
                          java.lang.Object value)
        Description copied from class: Printer
        Specified by:
        visit in class Printer
        Parameters:
        name - the value name.
        value - the actual value, whose type must be Byte, Boolean, Character, Short, Integer , Long, Float, Double, String or Type or OBJECT or ARRAY sort. This value can also be an array of byte, boolean, short, char, int, long, float or double values (this is equivalent to using visitArray and visiting each array element in turn, but is more convenient).
      • visitArray

        public ASMifier visitArray​(java.lang.String name)
        Description copied from class: Printer
        Annotation array value. See AnnotationVisitor.visitArray(java.lang.String). Visits an array value of the annotation. Note that arrays of primitive types (such as byte, boolean, short, char, int, long, float or double) can be passed as value to visit. This is what ClassReader does.
        Specified by:
        visitArray in class Printer
        Parameters:
        name - the value name.
        Returns:
        the printer
      • visitParameter

        public void visitParameter​(java.lang.String parameterName,
                                   int access)
        Description copied from class: Printer
        Overrides:
        visitParameter in class Printer
        Parameters:
        parameterName - parameter name or null if none is provided.
        access - the parameter's access flags, only ACC_FINAL, ACC_SYNTHETIC or/and ACC_MANDATED are allowed (see Opcodes).
      • visitFrame

        public void visitFrame​(int type,
                               int nLocal,
                               java.lang.Object[] local,
                               int nStack,
                               java.lang.Object[] stack)
        Description copied from class: Printer
        Method stack frame. See MethodVisitor.visitFrame(int, int, java.lang.Object[], int, java.lang.Object[]). Visits the current state of the local variables and operand stack elements. This method must(*) be called just before any instruction i that follows an unconditional branch instruction such as GOTO or THROW, that is the target of a jump instruction, or that starts an exception handler block. The visited types must describe the values of the local variables and of the operand stack elements just before i is executed.

        (*) this is mandatory only for classes whose version is greater than or equal to V1_6.

        The frames of a method must be given either in expanded form, or in compressed form (all frames must use the same format, i.e. you must not mix expanded and compressed frames within a single method):
        • In expanded form, all frames must have the F_NEW type.
        • In compressed form, frames are basically "deltas" from the state of the previous frame:
          • Opcodes.F_SAME representing frame with exactly the same locals as the previous frame and with the empty stack.
          • Opcodes.F_SAME1 representing frame with exactly the same locals as the previous frame and with single value on the stack ( nStack is 1 and stack[0] contains value for the type of the stack item).
          • Opcodes.F_APPEND representing frame with current locals are the same as the locals in the previous frame, except that additional locals are defined (nLocal is 1, 2 or 3 and local elements contains values representing added types).
          • Opcodes.F_CHOP representing frame with current locals are the same as the locals in the previous frame, except that the last 1-3 locals are absent and with the empty stack (nLocals is 1, 2 or 3).
          • Opcodes.F_FULL representing complete frame data.

        In both cases the first frame, corresponding to the method's parameters and access flags, is implicit and must not be visited. Also, it is illegal to visit two or more frames for the same code location (i.e., at least one instruction must be visited between two calls to visitFrame).
        Specified by:
        visitFrame in class Printer
        Parameters:
        type - the type of this stack map frame. Must be Opcodes.F_NEW for expanded frames, or Opcodes.F_FULL, Opcodes.F_APPEND, Opcodes.F_CHOP, Opcodes.F_SAME or Opcodes.F_APPEND, Opcodes.F_SAME1 for compressed frames.
        nLocal - the number of local variables in the visited frame.
        local - the local variable types in this frame. This array must not be modified. Primitive types are represented by Opcodes.TOP, Opcodes.INTEGER, Opcodes.FLOAT, Opcodes.LONG, Opcodes.DOUBLE,Opcodes.NULL or Opcodes.UNINITIALIZED_THIS (long and double are represented by a single element). Reference types are represented by String objects (representing internal names), and uninitialized types by Label objects (this label designates the NEW instruction that created this uninitialized value).
        nStack - the number of operand stack elements in the visited frame.
        stack - the operand stack types in this frame. This array must not be modified. Its content has the same format as the "local" array.
      • visitInsn

        public void visitInsn​(int opcode)
        Description copied from class: Printer
        Method instruction. See MethodVisitor.visitInsn(int)
        Specified by:
        visitInsn in class Printer
        Parameters:
        opcode - the opcode of the instruction to be visited. This opcode is either NOP, 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, IALOAD, LALOAD, FALOAD, DALOAD, AALOAD, BALOAD, CALOAD, SALOAD, IASTORE, LASTORE, FASTORE, DASTORE, AASTORE, BASTORE, CASTORE, SASTORE, POP, POP2, DUP, DUP_X1, DUP_X2, DUP2, DUP2_X1, DUP2_X2, SWAP, IADD, LADD, FADD, DADD, ISUB, LSUB, FSUB, DSUB, IMUL, LMUL, FMUL, DMUL, IDIV, LDIV, FDIV, DDIV, IREM, LREM, FREM, DREM, INEG, LNEG, FNEG, DNEG, ISHL, LSHL, ISHR, LSHR, IUSHR, LUSHR, IAND, LAND, IOR, LOR, IXOR, LXOR, I2L, I2F, I2D, L2I, L2F, L2D, F2I, F2L, F2D, D2I, D2L, D2F, I2B, I2C, I2S, LCMP, FCMPL, FCMPG, DCMPL, DCMPG, IRETURN, LRETURN, FRETURN, DRETURN, ARETURN, RETURN, ARRAYLENGTH, ATHROW, MONITORENTER, or MONITOREXIT.
      • visitVarInsn

        public void visitVarInsn​(int opcode,
                                 int var)
        Description copied from class: Printer
        Method instruction. See MethodVisitor.visitVarInsn(int, int).
        Specified by:
        visitVarInsn in class Printer
        Parameters:
        opcode - the opcode of the local variable instruction to be visited. This opcode is either ILOAD, LLOAD, FLOAD, DLOAD, ALOAD, ISTORE, LSTORE, FSTORE, DSTORE, ASTORE or RET.
        var - the operand of the instruction to be visited. This operand is the index of a local variable.
      • visitTypeInsn

        public void visitTypeInsn​(int opcode,
                                  java.lang.String type)
        Description copied from class: Printer
        Method instruction. See MethodVisitor.visitTypeInsn(int, java.lang.String). /** Visits a type instruction. A type instruction is an instruction that takes the internal name of a class as parameter.
        Specified by:
        visitTypeInsn in class Printer
        Parameters:
        opcode - the opcode of the type instruction to be visited. This opcode is either NEW, ANEWARRAY, CHECKCAST or INSTANCEOF.
        type - the operand of the instruction to be visited. This operand must be the internal name of an object or array class (see getInternalName).
      • visitMethodInsn

        public void visitMethodInsn​(int opcode,
                                    java.lang.String owner,
                                    java.lang.String name,
                                    java.lang.String desc,
                                    boolean itf)
        Description copied from class: Printer
        Overrides:
        visitMethodInsn in class Printer
        Parameters:
        opcode - the opcode of the type instruction to be visited. This opcode is either INVOKEVIRTUAL, INVOKESPECIAL, INVOKESTATIC or INVOKEINTERFACE.
        owner - the internal name of the method's owner class (see getInternalName).
        name - the method's name.
        desc - the method's descriptor (see Type).
        itf - if the method's owner class is an interface.
      • visitJumpInsn

        public void visitJumpInsn​(int opcode,
                                  Label label)
        Description copied from class: Printer
        Specified by:
        visitJumpInsn in class Printer
        Parameters:
        opcode - the opcode of the type instruction to be visited. This opcode is either IFEQ, IFNE, IFLT, IFGE, IFGT, IFLE, IF_ICMPEQ, IF_ICMPNE, IF_ICMPLT, IF_ICMPGE, IF_ICMPGT, IF_ICMPLE, IF_ACMPEQ, IF_ACMPNE, GOTO, JSR, IFNULL or IFNONNULL.
        label - the operand of the instruction to be visited. This operand is a label that designates the instruction to which the jump instruction may jump.
      • visitLdcInsn

        public void visitLdcInsn​(java.lang.Object cst)
        Description copied from class: Printer
        Method instruction. See MethodVisitor.visitLdcInsn(java.lang.Object). Visits a LDC instruction. Note that new constant types may be added in future versions of the Java Virtual Machine. To easily detect new constant types, implementations of this method should check for unexpected constant types, like this:
         if (cst instanceof Integer) {
             // ...
         } else if (cst instanceof Float) {
             // ...
         } else if (cst instanceof Long) {
             // ...
         } else if (cst instanceof Double) {
             // ...
         } else if (cst instanceof String) {
             // ...
         } else if (cst instanceof Type) {
             int sort = ((Type) cst).getSort();
             if (sort == Type.OBJECT) {
                 // ...
             } else if (sort == Type.ARRAY) {
                 // ...
             } else if (sort == Type.METHOD) {
                 // ...
             } else {
                 // throw an exception
             }
         } else if (cst instanceof Handle) {
             // ...
         } else {
             // throw an exception
         }
         
        Specified by:
        visitLdcInsn in class Printer
        Parameters:
        cst - the constant to be loaded on the stack. This parameter must be a non null Integer, a Float, a Long, a Double, a String, a Type of OBJECT or ARRAY sort for .class constants, for classes whose version is 49.0, a Type of METHOD sort or a Handle for MethodType and MethodHandle constants, for classes whose version is 51.0.
      • visitIincInsn

        public void visitIincInsn​(int var,
                                  int increment)
        Description copied from class: Printer
        Method instruction. See MethodVisitor.visitIincInsn(int, int).
        Specified by:
        visitIincInsn in class Printer
        Parameters:
        var - index of the local variable to be incremented.
        increment - amount to increment the local variable by.
      • visitLocalVariableAnnotation

        public Printer visitLocalVariableAnnotation​(int typeRef,
                                                    TypePath typePath,
                                                    Label[] start,
                                                    Label[] end,
                                                    int[] index,
                                                    java.lang.String desc,
                                                    boolean visible)
        Description copied from class: Printer
        Overrides:
        visitLocalVariableAnnotation in class Printer
        Parameters:
        typeRef - a reference to the annotated type. The sort of this type reference must be LOCAL_VARIABLE or RESOURCE_VARIABLE. See TypeReference.
        typePath - the path to the annotated type argument, wildcard bound, array element type, or static inner type within 'typeRef'. May be null if the annotation targets 'typeRef' as a whole.
        start - the fist instructions corresponding to the continuous ranges that make the scope of this local variable (inclusive).
        end - the last instructions corresponding to the continuous ranges that make the scope of this local variable (exclusive). This array must have the same size as the 'start' array.
        index - the local variable's index in each range. This array must have the same size as the 'start' array.
        desc - the class descriptor of the annotation class.
        visible - true if the annotation is visible at runtime.
        Returns:
        the printer
      • visitMaxs

        public void visitMaxs​(int maxStack,
                              int maxLocals)
        Description copied from class: Printer
        Method max stack and max locals. See MethodVisitor.visitMaxs(int, int).
        Specified by:
        visitMaxs in class Printer
        Parameters:
        maxStack - maximum stack size of the method.
        maxLocals - maximum number of local variables for the method.
      • visitAnnotation

        public ASMifier visitAnnotation​(java.lang.String desc,
                                        boolean visible)
      • visitTypeAnnotation

        public ASMifier visitTypeAnnotation​(int typeRef,
                                            TypePath typePath,
                                            java.lang.String desc,
                                            boolean visible)
      • visitTypeAnnotation

        public ASMifier visitTypeAnnotation​(java.lang.String method,
                                            int typeRef,
                                            TypePath typePath,
                                            java.lang.String desc,
                                            boolean visible)
      • visitAttribute

        public void visitAttribute​(Attribute attr)
      • createASMifier

        protected ASMifier createASMifier​(java.lang.String name,
                                          int id)
      • appendConstant

        protected void appendConstant​(java.lang.Object cst)
        Appends a string representation of the given constant to the given buffer.
        Parameters:
        cst - an Integer, Float, Long, Double or String object. May be null.
      • declareLabel

        protected void declareLabel​(Label l)
        Appends a declaration of the given label to buf. This declaration is of the form "Label lXXX = new Label();". Does nothing if the given label has already been declared.
        Parameters:
        l - a label.
      • appendLabel

        protected void appendLabel​(Label l)
        Appends the name of the given label to buf. The given label must already have a name. One way to ensure this is to always call declared before calling this method.
        Parameters:
        l - a label.