# Class InvokeInstruction

java.lang.Object
org.apache.bcel.generic.Instruction
org.apache.bcel.generic.CPInstruction
org.apache.bcel.generic.FieldOrMethod
org.apache.bcel.generic.InvokeInstruction

All Implemented Interfaces:
  `Cloneable, ExceptionThrower, IndexedInstruction, LoadClass, StackConsumer, StackProducer, TypedInstruction`

Direct Known Subclasses:
  `INVOKEDYNAMIC, INVOKEINTERFACE, INVOKESPECIAL, INVOKESTATIC, INVOKEVIRTUAL`

public abstract class InvokeInstruction extends FieldOrMethod implements ExceptionThrower, StackConsumer, StackProducer
Super class for the INVOKExxx family of instructions.

- ## Field Summary

  ### Fields inherited from class CPInstruction

  `index`

  ### Fields inherited from class Instruction

  `length, opcode`

- ## Constructor Summary

  Constructors
  Modifier
  Constructor
  Description
  `protected`
  `InvokeInstruction(short opcode, int index)`

- ## Method Summary

  Modifier and Type
  Method
  Description
  `int`
  `consumeStack(ConstantPoolGen cpg)`
  Also works for instructions whose stack effect depends on the constant pool entry they reference.
  `Type[]`
  `getArgumentTypes(ConstantPoolGen cpg)`
  `String`
  `getClassName(ConstantPoolGen cpg)`
  This overrides the deprecated version as we know here that the referenced class may legally be an array.
  `String`
  `getMethodName(ConstantPoolGen cpg)`
  `Type`
  `getReturnType(ConstantPoolGen cpg)`
  `Type`
  `getType(ConstantPoolGen cpg)`
  Returns the type associated with this instruction.
  `int`
  `produceStack(ConstantPoolGen cpg)`
  Also works for instructions whose stack effect depends on the constant pool entry they reference.
  `String`
  `toString(ConstantPool cp)`

  ### Methods inherited from class FieldOrMethod

  `getClassType, getLoadClassType, getName, getReferenceType, getSignature`

  ### Methods inherited from class CPInstruction

  `dump, getIndex, initFromFile, setIndex, toString`

  ### Methods inherited from class Instruction

  `accept, copy, equals, getComparator, getLength, getName, getOpcode, hashCode, isValidByte, isValidShort, readInstruction, setComparator, toString`

  ### Methods inherited from class Object

  `clone, finalize, getClass, notify, notifyAll, wait, wait, wait`

  ### Methods inherited from interface ExceptionThrower

  `getExceptions`

- ## Constructor Details

  - ### InvokeInstruction

    protected InvokeInstruction(short opcode, int index)
    Parameters:
      `index` - to constant pool

- ## Method Details

  - ### consumeStack

    public int consumeStack(ConstantPoolGen cpg)
    Also works for instructions whose stack effect depends on the constant pool entry they reference.
    Specified by:
      `consumeStack` in interface `StackConsumer`
    Overrides:
      `consumeStack` in class `Instruction`
    Returns:
      Number of words consumed from stack by this instruction

  - ### getArgumentTypes

    public Type[] getArgumentTypes(ConstantPoolGen cpg)
    Returns:
      argument types of referenced method.

  - ### getClassName

    public String getClassName(ConstantPoolGen cpg)
    This overrides the deprecated version as we know here that the referenced class may legally be an array.
    Overrides:
      `getClassName` in class `FieldOrMethod`
    Returns:
      name of the referenced class/interface
    Throws:
      `IllegalArgumentException` - if the referenced class is an array (this should not happen)

  - ### getMethodName

    public String getMethodName(ConstantPoolGen cpg)
    Returns:
      name of referenced method.

  - ### getReturnType

    public Type getReturnType(ConstantPoolGen cpg)
    Returns:
      return type of referenced method.

  - ### getType

    public Type getType(ConstantPoolGen cpg)
    Description copied from interface: `LoadClass`
    Returns the type associated with this instruction. LoadClass instances are always typed, but this type does not always refer to the type of the class or interface that it possibly forces to load. For example, `GETFIELD` would return the type of the field and not the type of the class where the field is defined. If no class is forced to be loaded, `null` is returned. An example for this is an `NEWARRAY` instruction that creates an `int[][]`.
    Specified by:
      `getType` in interface `LoadClass`
    Specified by:
      `getType` in interface `TypedInstruction`
    Overrides:
      `getType` in class `CPInstruction`
    Parameters:
      `cpg` - A ConstantPoolGen
    Returns:
      return type of referenced method.
    See Also:
      - `LoadClass.getLoadClassType(ConstantPoolGen)`

  - ### produceStack

    public int produceStack(ConstantPoolGen cpg)
    Also works for instructions whose stack effect depends on the constant pool entry they reference.
    Specified by:
      `produceStack` in interface `StackProducer`
    Overrides:
      `produceStack` in class `Instruction`
    Returns:
      Number of words produced onto stack by this instruction

  - ### toString

    public String toString(ConstantPool cp)
    Overrides:
      `toString` in class `CPInstruction`
    Returns:
      mnemonic for instruction with symbolic references resolved