Package org.apache.bcel.generic

Class ConstantPoolGen

  • public class ConstantPoolGen
extends java.lang.Object
    This class is used to build up a constant pool. The user adds constants via 'addXXX' methods, 'addString', 'addClass', etc.. These methods return an index into the constant pool. Finally, 'getFinalConstantPool()' returns the constant pool built up. Intermediate versions of the constant pool can be obtained with 'getConstantPool()'. A constant pool has capacity for Constants.MAX_SHORT entries. Note that the first (0) is used by the JVM and that Double and Long constants need two slots.
    See Also:
    Constant

    • Field Summary

      Fields 
      Modifier and Type Field Description
      protected Constant[] constants
      Deprecated.
      (since 6.0) will be made private; do not access directly, use getter/setter
      protected int index
      Deprecated.
      (since 6.0) will be made private; do not access directly, use getSize()
      protected int size
      Deprecated.
      (since 6.0) will be made private; do not access directly, use getter/setter

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      int addArrayClass​(ArrayType type)
      Add a reference to an array class (e.g.
      int addClass​(java.lang.String str)
      Add a new Class reference to the ConstantPool, if it is not already in there.
      int addClass​(ObjectType type)
      Add a new Class reference to the ConstantPool for a given type.
      int addConstant​(Constant constant, ConstantPoolGen cpGen)
      Adds a constant from another ConstantPool and returns the new index.
      int addDouble​(double n)
      Add a new double constant to the ConstantPool, if it is not already in there.
      int addFieldref​(java.lang.String className, java.lang.String fieldName, java.lang.String signature)
      Add a new Fieldref constant to the ConstantPool, if it is not already in there.
      int addFloat​(float n)
      Add a new Float constant to the ConstantPool, if it is not already in there.
      int addInteger​(int n)
      Add a new Integer constant to the ConstantPool, if it is not already in there.
      int addInterfaceMethodref​(java.lang.String className, java.lang.String methodName, java.lang.String signature)
      Add a new InterfaceMethodref constant to the ConstantPool, if it is not already in there.
      int addInterfaceMethodref​(MethodGen method)  
      int addLong​(long n)
      Add a new long constant to the ConstantPool, if it is not already in there.
      int addMethodref​(java.lang.String className, java.lang.String methodName, java.lang.String signature)
      Add a new Methodref constant to the ConstantPool, if it is not already in there.
      int addMethodref​(MethodGen method)  
      int addNameAndType​(java.lang.String name, java.lang.String signature)
      Add a new NameAndType constant to the ConstantPool if it is not already in there.
      int addString​(java.lang.String str)
      Add a new String constant to the ConstantPool, if it is not already in there.
      int addUtf8​(java.lang.String n)
      Add a new Utf8 constant to the ConstantPool, if it is not already in there.
      protected void adjustSize()
      Resize internal array of constants.
      Constant getConstant​(int i)  
      ConstantPool getConstantPool()  
      ConstantPool getFinalConstantPool()  
      int getSize()  
      int lookupClass​(java.lang.String str)
      Look for ConstantClass in ConstantPool named 'str'.
      int lookupDouble​(double n)
      Look for ConstantDouble in ConstantPool.
      int lookupFieldref​(java.lang.String className, java.lang.String fieldName, java.lang.String signature)
      Look for ConstantFieldref in ConstantPool.
      int lookupFloat​(float n)
      Look for ConstantFloat in ConstantPool.
      int lookupInteger​(int n)
      Look for ConstantInteger in ConstantPool.
      int lookupInterfaceMethodref​(java.lang.String className, java.lang.String methodName, java.lang.String signature)
      Look for ConstantInterfaceMethodref in ConstantPool.
      int lookupInterfaceMethodref​(MethodGen method)  
      int lookupLong​(long n)
      Look for ConstantLong in ConstantPool.
      int lookupMethodref​(java.lang.String className, java.lang.String methodName, java.lang.String signature)
      Look for ConstantMethodref in ConstantPool.
      int lookupMethodref​(MethodGen method)  
      int lookupNameAndType​(java.lang.String name, java.lang.String signature)
      Look for ConstantNameAndType in ConstantPool.
      int lookupString​(java.lang.String str)
      Look for ConstantString in ConstantPool containing String 'str'.
      int lookupUtf8​(java.lang.String n)
      Look for ConstantUtf8 in ConstantPool.
      void setConstant​(int i, Constant c)
      Use with care!
      java.lang.String toString()  

      • Methods inherited from class java.lang.Object

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

    • Field Detail

      • size

        @Deprecated
protected int size
        Deprecated.
        (since 6.0) will be made private; do not access directly, use getter/setter

      • constants

        @Deprecated
protected Constant[] constants
        Deprecated.
        (since 6.0) will be made private; do not access directly, use getter/setter

      • index

        @Deprecated
protected int index
        Deprecated.
        (since 6.0) will be made private; do not access directly, use getSize()

    • Constructor Detail

      • ConstantPoolGen

        public ConstantPoolGen()
        Constructs a new empty constant pool.

      • ConstantPoolGen

        public ConstantPoolGen​(Constant[] cs)
        Constructs a new instance with the given array of constants.
        Parameters:
        cs - array of given constants, new ones will be appended

      • ConstantPoolGen

        public ConstantPoolGen​(ConstantPool cp)
        Constructs a new instance with the given constant pool.
        Parameters:
        cp - the constant pool.

    • Method Detail

      • addArrayClass

        public int addArrayClass​(ArrayType type)
        Add a reference to an array class (e.g. String[][]) as needed by MULTIANEWARRAY instruction, e.g. to the ConstantPool.
        Parameters:
        type - type of array class
        Returns:
        index of entry

      • addClass

        public int addClass​(ObjectType type)
        Add a new Class reference to the ConstantPool for a given type.
        Parameters:
        type - Class to add
        Returns:
        index of entry

      • addClass

        public int addClass​(java.lang.String str)
        Add a new Class reference to the ConstantPool, if it is not already in there.
        Parameters:
        str - Class to add
        Returns:
        index of entry

      • addConstant

        public int addConstant​(Constant constant,
                       ConstantPoolGen cpGen)
        Adds a constant from another ConstantPool and returns the new index.
        Parameters:
        constant - The constant to add.
        cpGen - Source pool.
        Returns:
        index of entry

      • addDouble

        public int addDouble​(double n)
        Add a new double constant to the ConstantPool, if it is not already in there.
        Parameters:
        n - Double number to add
        Returns:
        index of entry

      • addFieldref

        public int addFieldref​(java.lang.String className,
                       java.lang.String fieldName,
                       java.lang.String signature)
        Add a new Fieldref constant to the ConstantPool, if it is not already in there.
        Parameters:
        className - class name string to add
        fieldName - field name string to add
        signature - signature string to add
        Returns:
        index of entry

      • addFloat

        public int addFloat​(float n)
        Add a new Float constant to the ConstantPool, if it is not already in there.
        Parameters:
        n - Float number to add
        Returns:
        index of entry

      • addInteger

        public int addInteger​(int n)
        Add a new Integer constant to the ConstantPool, if it is not already in there.
        Parameters:
        n - integer number to add
        Returns:
        index of entry

      • addInterfaceMethodref

        public int addInterfaceMethodref​(java.lang.String className,
                                 java.lang.String methodName,
                                 java.lang.String signature)
        Add a new InterfaceMethodref constant to the ConstantPool, if it is not already in there.
        Parameters:
        className - class name string to add
        methodName - method name string to add
        signature - signature string to add
        Returns:
        index of entry

      • addLong

        public int addLong​(long n)
        Add a new long constant to the ConstantPool, if it is not already in there.
        Parameters:
        n - Long number to add
        Returns:
        index of entry

      • addMethodref

        public int addMethodref​(java.lang.String className,
                        java.lang.String methodName,
                        java.lang.String signature)
        Add a new Methodref constant to the ConstantPool, if it is not already in there.
        Parameters:
        className - class name string to add
        methodName - method name string to add
        signature - method signature string to add
        Returns:
        index of entry

      • addNameAndType

        public int addNameAndType​(java.lang.String name,
                          java.lang.String signature)
        Add a new NameAndType constant to the ConstantPool if it is not already in there.
        Parameters:
        name - Name string to add
        signature - signature string to add
        Returns:
        index of entry

      • addString

        public int addString​(java.lang.String str)
        Add a new String constant to the ConstantPool, if it is not already in there.
        Parameters:
        str - String to add
        Returns:
        index of entry

      • addUtf8

        public int addUtf8​(java.lang.String n)
        Add a new Utf8 constant to the ConstantPool, if it is not already in there.
        Parameters:
        n - Utf8 string to add
        Returns:
        index of entry

      • adjustSize

        protected void adjustSize()
        Resize internal array of constants.

      • getConstant

        public Constant getConstant​(int i)
        Parameters:
        i - index in constant pool
        Returns:
        constant pool entry at index i

      • getSize

        public int getSize()
        Returns:
        current size of constant pool

      • lookupClass

        public int lookupClass​(java.lang.String str)
        Look for ConstantClass in ConstantPool named 'str'.
        Parameters:
        str - String to search for
        Returns:
        index on success, -1 otherwise

      • lookupDouble

        public int lookupDouble​(double n)
        Look for ConstantDouble in ConstantPool.
        Parameters:
        n - Double number to look for
        Returns:
        index on success, -1 otherwise

      • lookupFieldref

        public int lookupFieldref​(java.lang.String className,
                          java.lang.String fieldName,
                          java.lang.String signature)
        Look for ConstantFieldref in ConstantPool.
        Parameters:
        className - Where to find method
        fieldName - Guess what
        signature - return and argument types
        Returns:
        index on success, -1 otherwise

      • lookupFloat

        public int lookupFloat​(float n)
        Look for ConstantFloat in ConstantPool.
        Parameters:
        n - Float number to look for
        Returns:
        index on success, -1 otherwise

      • lookupInteger

        public int lookupInteger​(int n)
        Look for ConstantInteger in ConstantPool.
        Parameters:
        n - integer number to look for
        Returns:
        index on success, -1 otherwise

      • lookupInterfaceMethodref

        public int lookupInterfaceMethodref​(java.lang.String className,
                                    java.lang.String methodName,
                                    java.lang.String signature)
        Look for ConstantInterfaceMethodref in ConstantPool.
        Parameters:
        className - Where to find method
        methodName - Guess what
        signature - return and argument types
        Returns:
        index on success, -1 otherwise

      • lookupLong

        public int lookupLong​(long n)
        Look for ConstantLong in ConstantPool.
        Parameters:
        n - Long number to look for
        Returns:
        index on success, -1 otherwise

      • lookupMethodref

        public int lookupMethodref​(java.lang.String className,
                           java.lang.String methodName,
                           java.lang.String signature)
        Look for ConstantMethodref in ConstantPool.
        Parameters:
        className - Where to find method
        methodName - Guess what
        signature - return and argument types
        Returns:
        index on success, -1 otherwise

      • lookupNameAndType

        public int lookupNameAndType​(java.lang.String name,
                             java.lang.String signature)
        Look for ConstantNameAndType in ConstantPool.
        Parameters:
        name - of variable/method
        signature - of variable/method
        Returns:
        index on success, -1 otherwise

      • lookupString

        public int lookupString​(java.lang.String str)
        Look for ConstantString in ConstantPool containing String 'str'.
        Parameters:
        str - String to search for
        Returns:
        index on success, -1 otherwise

      • lookupUtf8

        public int lookupUtf8​(java.lang.String n)
        Look for ConstantUtf8 in ConstantPool.
        Parameters:
        n - Utf8 string to look for
        Returns:
        index on success, -1 otherwise

      • setConstant

        public void setConstant​(int i,
                        Constant c)
        Use with care!
        Parameters:
        i - index in constant pool
        c - new constant pool entry at index i

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object
        Returns:
        String representation.