Module openj9.dtfj

Package com.ibm.dtfj.corereaders.j9

Class Memory

java.lang.Object

com.ibm.dtfj.corereaders.j9.Memory

public class Memory
extends Object

Memory adapter which removes the need for a component to know the address space ID that it is working with. This is set when the adapter is created.

Constructor Summary

Constructors

Constructor	Description
Memory(IAbstractAddressSpace space)	Create a memory representation

Method Summary

Modifier and Type	Method	Description
int	bytesPerPointer()	Identify the memory as 32 or 64 bit
long	findPattern(byte[] whatBytes, int alignment, long startFrom)	Search the memory for a specific byte pattern
byte	getByteAt(long address)	Read a byte from the specified address
int	getBytesAt(long address, byte[] buffer)	Read a byte from the specified address
int	getIntAt(long address)	Read an int from the specified address
long	getLongAt(long address)	Read a long from the specified address
byte[]	getMemoryBytes(long address, int size)	Read bytes from the specified address
Iterator	getMemoryRanges()	Get the memory ranges for this address space
long	getPointerAt(long address)	Read a pointer at the specified address
short	getShortAt(long address)	Read a short from the specified address
boolean	isExecutable(long address)	Flag for executable memory
boolean	isReadOnly(long address)	Flag to indicate if the memory is read only
boolean	isShared(long address)	Flag to indicate if the memory is shared

Methods declared in class java.lang.Object

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

Constructor Detail

Memory

public Memory(IAbstractAddressSpace space)

Create a memory representation

Parameters:

space - the underlying address space

Method Detail

bytesPerPointer

public int bytesPerPointer()

Identify the memory as 32 or 64 bit

Returns:

4 for 31/32 bit, 8 for 64 bit

findPattern

public long findPattern(byte[] whatBytes,
                        int alignment,
                        long startFrom)

Search the memory for a specific byte pattern

Parameters:

whatBytes - what to search for

alignment - byte alignment

startFrom - position to start the search from

Returns:

the address of the bytes if found or -1

getByteAt

public byte getByteAt(long address)
               throws MemoryAccessException

Read a byte from the specified address

Parameters:

address - address to read from

Returns:

the data

Throws:

MemoryAccessException

getBytesAt

public int getBytesAt(long address,
                      byte[] buffer)
               throws MemoryAccessException

Read a byte from the specified address

Parameters:

address - address to read from

Returns:

the data

Throws:

MemoryAccessException

getIntAt

public int getIntAt(long address)
             throws MemoryAccessException

Read an int from the specified address

Parameters:

address - address to read from

Returns:

the data

Throws:

MemoryAccessException

getLongAt

public long getLongAt(long address)
               throws MemoryAccessException

Read a long from the specified address

Parameters:

address - address to read from

Returns:

the data

Throws:

MemoryAccessException

getMemoryBytes

public byte[] getMemoryBytes(long address,
                             int size)

Read bytes from the specified address

Parameters:

address - address to read from

size - number of bytes to read

Returns:

the data

getMemoryRanges

public Iterator getMemoryRanges()

Get the memory ranges for this address space

getPointerAt

public long getPointerAt(long address)
                  throws MemoryAccessException

Read a pointer at the specified address

Parameters:

address - address to read from

Returns:

the data

Throws:

MemoryAccessException

getShortAt

public short getShortAt(long address)
                 throws MemoryAccessException

Read a short from the specified address

Parameters:

address - address to read from

Returns:

the data

Throws:

MemoryAccessException

isExecutable

public boolean isExecutable(long address)
                     throws MemoryAccessException

Flag for executable memory

Returns:

true if it is executable

Throws:

MemoryAccessException

isReadOnly

public boolean isReadOnly(long address)
                   throws MemoryAccessException

Flag to indicate if the memory is read only

Returns:

true if it is read only

Throws:

MemoryAccessException

isShared

public boolean isShared(long address)
                 throws MemoryAccessException

Flag to indicate if the memory is shared

Returns:

true if it is shared

Throws:

MemoryAccessException