Module openj9.dtfj

Package com.ibm.dtfj.corereaders.zos.dumpreader

Class Dump

java.lang.Object

javax.imageio.stream.ImageInputStreamImpl

com.ibm.dtfj.corereaders.zos.dumpreader.Dump

All Implemented Interfaces:

Closeable, DataInput, AutoCloseable, ImageInputStream

public final class Dump
extends ImageInputStreamImpl

This class represents an svcdump. It is the main class in the dumpreader package and provides low-level access to the contents of an svcdump (eg the ability to read the contents of an address in a given address space).

Implementation note: currently implemented by linking to the old svcdump.jar code (so you need to include svcdump.jar when using) but this dependency will eventually be removed. Note: zebedee dependency on svcdump.jar has been removed

Field Summary

Fields declared in class javax.imageio.stream.ImageInputStreamImpl

bitOffset, byteOrder, flushedPos, streamPos

Constructor Summary

Constructors

Constructor	Description
Dump(String filename)	Creates a new instance of Dump from the given filename.
Dump(String filename, SearchListener[] listeners)	Creates a new instance of Dump from the given filename.
Dump(String filename, ImageInputStream stream, boolean createCacheFile)	Creates a new instance of Dump from the given filename.

Method Summary

Modifier and Type	Method	Description
AddressSpace[]	getAddressSpaces()	Returns an array of all the address spaces in the dump.
Date	getCreationDate()	Returns the time when the dump was created.
String	getProductModification()	Returns the z/OS product modification.
String	getProductName()	Returns the z/OS product name.
String	getProductRelease()	Returns the z/OS product release.
String	getProductVersion()	Returns the z/OS product version.
String	getTitle()	Returns the title of the dump.
boolean	is64bit()	Returns true if this is a 64-bit dump.
static boolean	isValid(String filename)	Returns true if the given filename is a valid svcdump.
long	length()	Get the length of the dump file
static Date	mvsClockToDate(long clock)	Convert an MVS style clock value to a Date object.
int	read()	Reads an unsigned byte from the file
int	read(byte[] buf)	Read from the dump file into the given buffer.
int	read(byte[] buf, int off, int len)	Read from the dump file into the given buffer.
void	seek(long offset)	Seek to the given offset in the dump file.

Methods declared in class javax.imageio.stream.ImageInputStreamImpl

checkClosed, close, finalize, flush, flushBefore, getBitOffset, getByteOrder, getFlushedPosition, getStreamPosition, isCached, isCachedFile, isCachedMemory, mark, readBit, readBits, readBoolean, readByte, readBytes, readChar, readDouble, readFloat, readFully, readFully, readFully, readFully, readFully, readFully, readFully, readFully, readInt, readLine, readLong, readShort, readUnsignedByte, readUnsignedInt, readUnsignedShort, readUTF, reset, setBitOffset, setByteOrder, skipBytes, skipBytes

Methods declared in class java.lang.Object

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

Constructor Details

Dump

public Dump(String filename)
     throws FileNotFoundException

Creates a new instance of Dump from the given filename. The filename must represent either an absolute or relative pathname of the dump file, or if running on z/os it can be an MVS dataset name (eg DGRIFF.MYDUMP).

Parameters:

filename - the name of the dump to open

Throws:

FileNotFoundException

Dump

public Dump(String filename,
 ImageInputStream stream,
 boolean createCacheFile)
     throws FileNotFoundException

Creates a new instance of Dump from the given filename. The filename must represent either an absolute or relative pathname of the dump file, or if running on z/os it can be an MVS dataset name (eg DGRIFF.MYDUMP). Alternatively an ImageInputStream can be provided if the file is already open.

Parameters:

filename - the name of the dump to open, also used to open the cache file

stream - an ImageInputStream for the dump or null - used in preference to opening the file

createCacheFile - Create a cache file based on the filename

Throws:

FileNotFoundException

Dump

public Dump(String filename,
 SearchListener[] listeners)
     throws FileNotFoundException

Creates a new instance of Dump from the given filename. The filename must represent either an absolute or relative pathname of the dump file, or if running on z/os it can be an MVS dataset name.

This constructor also supplies an array of SearchListeners to inform the caller of matches found whilst scanning the dump. Note that this will force a scan of the dump which is otherwise normally only done the first time this dump is opened. (XXX can probably avoid this by cacheing earlier search results).

Parameters:

filename - the name of the dump to open

listeners - the array of SearchListeners to be notified of interesting matches

Throws:

FileNotFoundException

Method Details

isValid

public static boolean isValid(String filename)

Returns true if the given filename is a valid svcdump.

seek

public void seek(long offset)
          throws IOException

Seek to the given offset in the dump file. This also handles MVS datasets in an efficient way (simply using fseek is too slow because the seek appears to read the file from the beginning every time!).

Specified by:

seek in interface ImageInputStream

Overrides:

seek in class ImageInputStreamImpl

Parameters:

offset - the offset to seek to

Throws:

IOException - if any other I/O error occurs.

read

public int read()
         throws IOException

Reads an unsigned byte from the file

Specified by:

read in interface ImageInputStream

Specified by:

read in class ImageInputStreamImpl

Returns:

Throws:

IOException

read

public int read(byte[] buf,
 int off,
 int len)
         throws IOException

Read from the dump file into the given buffer.

Specified by:

read in interface ImageInputStream

Specified by:

read in class ImageInputStreamImpl

Parameters:

buf - the buffer to read into

off - the offset into the buffer to start at

len - the maximum number of bytes to read

Returns:

the number of bytes actually read, or -1 to indicate EOF.

Throws:

IOException - if an I/O error occurs.

read

public int read(byte[] buf)
         throws IOException

Read from the dump file into the given buffer.

Specified by:

read in interface ImageInputStream

Overrides:

read in class ImageInputStreamImpl

Parameters:

buf - the buffer to read into

Returns:

the number of bytes actually read, or -1 to indicate EOF.

Throws:

IOException - if an I/O error occurs.

length

public long length()

Get the length of the dump file

Specified by:

length in interface ImageInputStream

Overrides:

length in class ImageInputStreamImpl

Returns:

-1L to indicate unknown length.

getAddressSpaces

public AddressSpace[] getAddressSpaces()

Returns an array of all the address spaces in the dump.

is64bit

public boolean is64bit()

Returns true if this is a 64-bit dump. Always returns false at the moment 'cos I haven't yet got my paws on a 64-bit dump.

getTitle

public String getTitle()

Returns the title of the dump.

getProductName

public String getProductName()

Returns the z/OS product name.

getProductVersion

public String getProductVersion()

Returns the z/OS product version.

getProductRelease

public String getProductRelease()

Returns the z/OS product release.

getProductModification

public String getProductModification()

Returns the z/OS product modification.

mvsClockToDate

public static Date mvsClockToDate(long clock)

Convert an MVS style clock value to a Date object.

getCreationDate

public Date getCreationDate()

Returns the time when the dump was created.