EDU.purdue.cs.bloat.file

Class ClassFile

java.lang.Object

EDU.purdue.cs.bloat.file.ClassFile

All Implemented Interfaces:

ClassInfo

public class ClassFile
extends java.lang.Object
implements ClassInfo

ClassFile basically represents a Java classfile as it is found on disk. The classfile is modeled according to the Java Virtual Machine Specification. Methods are provided to edit the classfile at a very low level.

See Also:

Attribute, Constant, Field, Method

Constructor Summary

Constructors

Constructor and Description
ClassFile(java.io.File file, ClassInfoLoader loader, java.io.DataInputStream in) Constructor.
ClassFile(int modifiers, int classIndex, int superClassIndex, int[] interfaceIndexes, java.util.List constants, ClassInfoLoader loader) Creates a new ClassFile from scratch.

Method Summary

Methods

Modifier and Type	Method and Description
FieldInfo	addNewField(int modifiers, int typeIndex, int nameIndex) Creates a new field in this classfile
FieldInfo	addNewField(int modifiers, int typeIndex, int nameIndex, int cvNameIndex, int constantValueIndex) Creates a new field in this classfile
MethodInfo	addNewMethod(int modifiers, int typeIndex, int nameIndex, int exceptionIndex, int[] exceptionTypeIndices, int codeIndex) Creates a new method in this class
int	classIndex() Get the index into the constant pool of the name of the class.
void	commit() Commit any changes back to a file in the output directory.
void	commitOnly(java.util.Set methods, java.util.Set fields) Commits only certain methods and fields.
Constant[]	constants() Get an array of the constants in the constant pool.
void	deleteField(int nameIndex) Removes the field whose name is at the given index in the constant pool.
void	deleteMethod(int nameIndex, int typeIndex) Deletes a method from this class
FieldInfo[]	fields() Get an array of FieldInfo structures for each field in the class.
java.io.File	file() Returns the File from which this ClassFile was created.
int[]	interfaceIndices() Get the indices into the constant pool of the names of the class's interfaces.
ClassInfoLoader	loader() Get the class info loader for the class.
MethodInfo[]	methods() Returns an array of MethodInfo structures for each method in the class.
int	modifiers() Get the modifiers of the class.
java.lang.String	name() Get the name of the class, including the package name.
java.io.File	outputFile() Creates a new File object to hold this class.
void	print(java.io.PrintStream out) Prints a textual representation of this classfile to a PrintStream.
void	print(java.io.PrintWriter out)
void	setClassIndex(int index) Set the index into the constant pool of the name of the class.
void	setConstants(Constant[] constants) Set all the constants in the constant pool.
void	setInterfaceIndices(int[] indices) Set the indices into the constant pool of the names of the class's interfaces.
void	setMethods(MethodInfo[] methods) Sets the methods in this class.
void	setModifiers(int modifiers) Set the modifiers of the class.
void	setSuperclassIndex(int index) Set the index into the constant pool of the name of the class's superclass.
int	superclassIndex() Get the index into the constant pool of the name of the class's superclass.
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

ClassFile

public ClassFile(java.io.File file,
         ClassInfoLoader loader,
         java.io.DataInputStream in)

Constructor. This constructor parses the class file from the input stream.

Parameters:

file - The file in which the class resides.

loader - The class info loader which loaded the class.

in - The data stream containing the class.

Throws:

java.lang.ClassFormatError - When the class could not be parsed.

ClassFile

public ClassFile(int modifiers,
         int classIndex,
         int superClassIndex,
         int[] interfaceIndexes,
         java.util.List constants,
         ClassInfoLoader loader)

Creates a new ClassFile from scratch. It has no fields or methods.

Parameters:

modifiers - The modifiers describing the newly-created class

classIndex - The index of the type of the newly-created class in its constant pool

superClassIndex - The index of the type of the newly-created class's superclass in its constant pool

interfaceIndexes - The indexes of the types of the interfaces that the newly-created class implements

constants - The constant pool for the newly created class (a list of Constants).

Method Detail

loader

public ClassInfoLoader loader()

Get the class info loader for the class.

Specified by:

loader in interface ClassInfo

Returns:

The class info loader for the class.

name

public java.lang.String name()

Get the name of the class, including the package name.

Specified by:

name in interface ClassInfo

Returns:

The name of the class.

setClassIndex

public void setClassIndex(int index)

Set the index into the constant pool of the name of the class.

Specified by:

setClassIndex in interface ClassInfo

Parameters:

index - The index of the name of the class.

setSuperclassIndex

public void setSuperclassIndex(int index)

Set the index into the constant pool of the name of the class's superclass.

Specified by:

setSuperclassIndex in interface ClassInfo

Parameters:

index - The index of the name of the superclass.

setInterfaceIndices

public void setInterfaceIndices(int[] indices)

Set the indices into the constant pool of the names of the class's interfaces.

Specified by:

setInterfaceIndices in interface ClassInfo

Parameters:

indices - The indices of the names of the interfaces.

classIndex

public int classIndex()

Get the index into the constant pool of the name of the class.

Specified by:

classIndex in interface ClassInfo

Returns:

The index of the name of the class.

superclassIndex

public int superclassIndex()

Get the index into the constant pool of the name of the class's superclass.

Specified by:

superclassIndex in interface ClassInfo

Returns:

The index of the name of the superclass.

interfaceIndices

public int[] interfaceIndices()

Get the indices into the constant pool of the names of the class's interfaces.

Specified by:

interfaceIndices in interface ClassInfo

Returns:

The indices of the names of the interfaces.

setModifiers

public void setModifiers(int modifiers)

Set the modifiers of the class. The values correspond to the constants in the Modifiers class.

Specified by:

setModifiers in interface ClassInfo

Parameters:

modifiers - A bit vector of modifier flags for the class.

See Also:

Modifiers

modifiers

public int modifiers()

Get the modifiers of the class. The values correspond to the constants in the Modifiers class.

Specified by:

modifiers in interface ClassInfo

Returns:

A bit vector of modifier flags for the class.

See Also:

Modifiers

fields

public FieldInfo[] fields()

Get an array of FieldInfo structures for each field in the class.

Specified by:

fields in interface ClassInfo

Returns:

An array of FieldInfo structures.

See Also:

FieldInfo

methods

public MethodInfo[] methods()

Returns an array of MethodInfo structures for each method in the class.

Specified by:

methods in interface ClassInfo

setMethods

public void setMethods(MethodInfo[] methods)

Sets the methods in this class.

Specified by:

setMethods in interface ClassInfo

constants

public Constant[] constants()

Get an array of the constants in the constant pool.

Specified by:

constants in interface ClassInfo

Returns:

An array of Constants.

setConstants

public void setConstants(Constant[] constants)

Set all the constants in the constant pool.

Specified by:

setConstants in interface ClassInfo

Parameters:

constants - The array of Constants.

See Also:

Constant

file

public java.io.File file()

Returns the File from which this ClassFile was created. If this ClassFile was created from scratch, null is returned.

outputFile

public java.io.File outputFile()

Creates a new File object to hold this class. It is placed in the output directory and has the name of the class represented by this ClassFile followed by the .class extension.

commit

public void commit()

Commit any changes back to a file in the output directory. The output directory is determined from the ClassFileLoader.

Specified by:

commit in interface ClassInfo

commitOnly

public void commitOnly(java.util.Set methods,
              java.util.Set fields)

Description copied from interface: ClassInfo

Commits only certain methods and fields.

Specified by:

commitOnly in interface ClassInfo

Parameters:

methods - Methods (MethodInfos) to commit. If null, all methods are committed.

fields - Fields (FieldInfos) to commit. If null, all fields are committed.

addNewField

public FieldInfo addNewField(int modifiers,
                    int typeIndex,
                    int nameIndex)

Creates a new field in this classfile

Specified by:

addNewField in interface ClassInfo

addNewField

public FieldInfo addNewField(int modifiers,
                    int typeIndex,
                    int nameIndex,
                    int cvNameIndex,
                    int constantValueIndex)

Creates a new field in this classfile

Specified by:

addNewField in interface ClassInfo

cvNameIndex - The index in the class's constant pool for the UTF8 constant "ConstantValue"

constantValueIndex - The index in the class's constant pool for the constant value

deleteField

public void deleteField(int nameIndex)

Removes the field whose name is at the given index in the constant pool.

Specified by:

deleteField in interface ClassInfo

Parameters:

nameIndex - Index in the constant pool of the name of the field to be deleted

Throws:

java.lang.IllegalArgumentException - The class does not contain a field whose name is at the given index

deleteMethod

public void deleteMethod(int nameIndex,
                int typeIndex)

Deletes a method from this class

Specified by:

deleteMethod in interface ClassInfo

Parameters:

nameIndex - Index in the constant pool of the name of the method to be deleted

typeIndex - Index in the constant pool of the type of the method to be deleted

Throws:

java.lang.IllegalArgumentException - The class modeled by this ClassInfo does not contain a method whose name and type are not at the given indices

addNewMethod

public MethodInfo addNewMethod(int modifiers,
                      int typeIndex,
                      int nameIndex,
                      int exceptionIndex,
                      int[] exceptionTypeIndices,
                      int codeIndex)

Creates a new method in this class

Specified by:

addNewMethod in interface ClassInfo

Parameters:

modifiers - The modifiers for the new method

typeIndex - The index of the type (conglomeration of the parameter types and the return type) for this method in the class's constant pool

nameIndex - The index of the name of the method in the class's constant pool

exceptionIndex - The index of the UTF8 string "Exceptions" in the class's constant pool

exceptionTypeIndices - The indices in the class's constant pool of the type of the exceptions thrown by this method

codeIndex - The index of the UTF8 string "Code" in the class's constant pool

print

public void print(java.io.PrintStream out)

Prints a textual representation of this classfile to a PrintStream. The text includes information such as the constants in the constant pool, the name of the class's superclass, its modifier flags, its fields, and its methods.

Specified by:

print in interface ClassInfo

Parameters:

out - The stream to which to print.

print

public void print(java.io.PrintWriter out)

Specified by:

print in interface ClassInfo

toString

public java.lang.String toString()

Specified by:

toString in interface ClassInfo

Overrides:

toString in class java.lang.Object