org.jikesrvm.classloader

Class ClassFileReader

java.lang.Object

org.jikesrvm.classloader.ClassFileReader

public class ClassFileReader
extends Object

Support code to parse a DataInputStream in the Java classfile format and create the appropriate instance of an RVMClass or UnboxedType. Also low-level support for our internal constant pool format.

Constructor Summary

Constructors

Constructor and Description
ClassFileReader()

Method Summary

Modifier and Type	Method and Description
(package private) static RVMMethod	getClassInitializerMethod(RVMMethod[] declaredMethods) Returns the class initializer method among the declared methods of the class
(package private) static FieldReference	getFieldRef(int[] constantPool, int constantPoolIndex)
(package private) static byte	getLiteralDescription(int[] constantPool, int constantPoolIndex)
(package private) static Offset	getLiteralOffset(int[] constantPool, int constantPoolIndex) Get offset of a literal constant, in bytes.
(package private) static int	getLiteralSize(int[] constantPool, int constantPoolIndex)
(package private) static MethodReference	getMethodRef(int[] constantPool, int constantPoolIndex)
(package private) static TypeReference	getTypeRef(int[] constantPool, int constantPoolIndex)
(package private) static Atom	getUtf(int[] constantPool, int constantPoolIndex)
(package private) static int	packCPEntry(byte type, int value)
(package private) static boolean	packedCPTypeIsClassType(int cpValue)
(package private) static int	packTempCPEntry(int index1, int index2)
(package private) static RVMClass	readClass(TypeReference typeRef, DataInputStream input) Creates an instance of a RVMClass.
(package private) static int[]	readConstantPool(TypeReference typeRef, DataInputStream input) Parse and return the constant pool in a class file
(package private) static RVMField[]	readDeclaredFields(TypeReference typeRef, DataInputStream input, int[] constantPool)
(package private) static RVMClass[]	readDeclaredInterfaces(DataInputStream input, int[] constantPool)
(package private) static RVMMethod[]	readDeclaredMethods(TypeReference typeRef, DataInputStream input, int[] constantPool)
(package private) static RVMClass	readSuperClass(DataInputStream input, int[] constantPool, short modifiers)
(package private) static int	readTypeRef(TypeReference typeRef, DataInputStream input, int[] constantPool) Read the class' TypeReference
(package private) static byte	unpackCPType(int cpValue)
(package private) static int	unpackSignedCPValue(int cpValue)
(package private) static int	unpackTempCPIndex1(int cpValue)
(package private) static int	unpackTempCPIndex2(int cpValue)
(package private) static int	unpackUnsignedCPValue(int cpValue)

Methods inherited from class java.lang.Object

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

Constructor Detail

ClassFileReader

public ClassFileReader()

Method Detail

readConstantPool

static int[] readConstantPool(TypeReference typeRef,
                              DataInputStream input)
                       throws ClassFormatError,
                              IOException

Parse and return the constant pool in a class file

Parameters:

typeRef - the canonical type reference for this type.

input - the data stream from which to read the class's description.

Returns:

constant pool as int array

Throws:

IOException - if it occurs during reading of the input stream

ClassFormatError

readTypeRef

static int readTypeRef(TypeReference typeRef,
                       DataInputStream input,
                       int[] constantPool)
                throws IOException,
                       ClassFormatError

Read the class' TypeReference

Parameters:

typeRef - the type reference that we're expecting to read

input - input stream

constantPool - constant pool

Returns:

the constantPool index of the typeRef of the class we are reading

Throws:

IOException - when a problems occurs while reading the input stream

ClassFormatError - when the read type ref does not match up with the expected type ref

readSuperClass

static RVMClass readSuperClass(DataInputStream input,
                               int[] constantPool,
                               short modifiers)
                        throws IOException,
                               NoClassDefFoundError

Throws:

IOException

NoClassDefFoundError

readDeclaredInterfaces

static RVMClass[] readDeclaredInterfaces(DataInputStream input,
                                         int[] constantPool)
                                  throws IOException,
                                         NoClassDefFoundError

Throws:

IOException

NoClassDefFoundError

readDeclaredFields

static RVMField[] readDeclaredFields(TypeReference typeRef,
                                     DataInputStream input,
                                     int[] constantPool)
                              throws IOException

Throws:

IOException

readDeclaredMethods

static RVMMethod[] readDeclaredMethods(TypeReference typeRef,
                                       DataInputStream input,
                                       int[] constantPool)
                                throws IOException

Throws:

IOException

getClassInitializerMethod

static RVMMethod getClassInitializerMethod(RVMMethod[] declaredMethods)

Returns the class initializer method among the declared methods of the class

Parameters:

declaredMethods - the methods declared by the class

Returns:

the class initializer method <clinit> of the class or null if none was found

readClass

static RVMClass readClass(TypeReference typeRef,
                          DataInputStream input)
                   throws ClassFormatError,
                          IOException

Creates an instance of a RVMClass.

Parameters:

typeRef - the canonical type reference for this type.

input - the data stream from which to read the class's description.

Returns:

a newly created class

Throws:

IOException - when data cannot be read from the input stream or skipping during class construction reads less data than expected

ClassFormatError - when the class data is corrupt

packCPEntry

static int packCPEntry(byte type,
                       int value)

unpackCPType

static byte unpackCPType(int cpValue)

unpackSignedCPValue

static int unpackSignedCPValue(int cpValue)

unpackUnsignedCPValue

static int unpackUnsignedCPValue(int cpValue)

packedCPTypeIsClassType

static boolean packedCPTypeIsClassType(int cpValue)

packTempCPEntry

static int packTempCPEntry(int index1,
                           int index2)

unpackTempCPIndex1

static int unpackTempCPIndex1(int cpValue)

unpackTempCPIndex2

static int unpackTempCPIndex2(int cpValue)

getLiteralSize

static int getLiteralSize(int[] constantPool,
                          int constantPoolIndex)

getLiteralOffset

static Offset getLiteralOffset(int[] constantPool,
                               int constantPoolIndex)

Get offset of a literal constant, in bytes. Offset is with respect to virtual machine's "table of contents" (jtoc).

Parameters:

constantPool - the constant pool

constantPoolIndex - the index into the constant pool

Returns:

the offset in bytes from the JTOC

getLiteralDescription

static byte getLiteralDescription(int[] constantPool,
                                  int constantPoolIndex)

getTypeRef

static TypeReference getTypeRef(int[] constantPool,
                                int constantPoolIndex)

getMethodRef

static MethodReference getMethodRef(int[] constantPool,
                                    int constantPoolIndex)

getFieldRef

static FieldReference getFieldRef(int[] constantPool,
                                  int constantPoolIndex)

getUtf

static Atom getUtf(int[] constantPool,
                   int constantPoolIndex)