Package org.apache.bcel.generic

Class ConstantPoolGen

  • public class ConstantPoolGen
extends 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 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​(Constant[] cs)
        Initialize with given array of constants.
        Parameters:
        cs - array of given constants, new ones will be appended

      • ConstantPoolGen

        public ConstantPoolGen​(ConstantPool cp)
        Initialize with given constant pool.

      • ConstantPoolGen

        public ConstantPoolGen()
        Create empty constant pool.

    • Method Detail

      • adjustSize

        protected void adjustSize()
        Resize internal array of constants.

      • lookupString

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

      • addString

        public int addString​(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

      • lookupClass

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

      • addClass

        public int addClass​(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

      • 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

      • 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

      • lookupInteger

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

      • 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

      • lookupFloat

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

      • 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

      • lookupUtf8

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

      • addUtf8

        public int addUtf8​(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

      • lookupLong

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

      • 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

      • lookupDouble

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

      • 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

      • lookupNameAndType

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

      • addNameAndType

        public int addNameAndType​(String name,
                          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

      • lookupMethodref

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

      • lookupMethodref

        public int lookupMethodref​(MethodGen method)

      • addMethodref

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

      • addMethodref

        public int addMethodref​(MethodGen method)

      • lookupInterfaceMethodref

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

      • lookupInterfaceMethodref

        public int lookupInterfaceMethodref​(MethodGen method)

      • addInterfaceMethodref

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

      • addInterfaceMethodref

        public int addInterfaceMethodref​(MethodGen method)

      • lookupFieldref

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

      • addFieldref

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

      • getConstant

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

      • 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

      • getConstantPool

        public ConstantPool getConstantPool()
        Returns:
        intermediate constant pool

      • getSize

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

      • getFinalConstantPool

        public ConstantPool getFinalConstantPool()
        Returns:
        constant pool with proper length

      • toString

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

      • addConstant

        public int addConstant​(Constant c,
                       ConstantPoolGen cp)
        Import constant from another ConstantPool and return new index.