Package org.objectweb.asm.tree.analysis

Class BasicVerifier

java.lang.Object
org.objectweb.asm.tree.analysis.Interpreter<BasicValue>
org.objectweb.asm.tree.analysis.BasicInterpreter
org.objectweb.asm.tree.analysis.BasicVerifier
All Implemented Interfaces:
Opcodes
Direct Known Subclasses:
SimpleVerifier
public class BasicVerifier extends BasicInterpreter
An extended BasicInterpreter that checks that bytecode instructions are correctly used.

  • Constructor Details

    • BasicVerifier

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

    • BasicVerifier

      protected BasicVerifier(int api)
      Constructs a new BasicVerifier.
      Parameters:
      api - the ASM API version supported by this interpreter. Must be one of the ASMx values in Opcodes.

  • Method Details

    • copyOperation

      public BasicValue copyOperation(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

      Overrides:
      copyOperation in class BasicInterpreter
      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(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

      Overrides:
      unaryOperation in class BasicInterpreter
      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(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

      Overrides:
      binaryOperation in class BasicInterpreter
      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(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

      Overrides:
      ternaryOperation in class BasicInterpreter
      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(AbstractInsnNode insn, 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

      Overrides:
      naryOperation in class BasicInterpreter
      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(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

      Overrides:
      returnOperation in class BasicInterpreter
      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.

    • isArrayValue

      protected boolean isArrayValue(BasicValue value)
      Returns whether the given value corresponds to an array reference.
      Parameters:
      value - a value.
      Returns:
      whether 'value' corresponds to an array reference.

    • getElementValue

      protected BasicValue getElementValue(BasicValue objectArrayValue) throws AnalyzerException
      Returns the value corresponding to the type of the elements of the given array reference value.
      Parameters:
      objectArrayValue - a value corresponding to array of object (or array) references.
      Returns:
      the value corresponding to the type of the elements of 'objectArrayValue'.
      Throws:
      AnalyzerException - if objectArrayValue does not correspond to an array type.

    • isSubTypeOf

      protected boolean isSubTypeOf(BasicValue value, BasicValue expected)
      Returns whether the type corresponding to the first argument is a subtype of the type corresponding to the second argument.
      Parameters:
      value - a value.
      expected - another value.
      Returns:
      whether the type corresponding to 'value' is a subtype of the type corresponding to 'expected'.