Module openj9.dtfjview

Package com.ibm.jvm.dtfjview.commands

Class BaseJdmpviewCommand

java.lang.Object

com.ibm.java.diagnostics.utils.commands.BaseCommand

com.ibm.jvm.dtfjview.commands.BaseJdmpviewCommand

All Implemented Interfaces:

ICommand

Direct Known Subclasses:

CdCommand, CloseCommand, DeadlockCommand, FindCommand, FindNextCommand, FindPtrCommand, HeapdumpCommand, HelpCommand, HexdumpCommand, InfoClassCommand, InfoHeapCommand, InfoJitmCommand, InfoLockCommand, InfoMemoryCommand, InfoMmapCommand, InfoProcCommand, InfoSymCommand, InfoSystemCommand, InfoThreadCommand, LogCommand, OpenCommand, PwdCommand, ScrollCommand, SetHeapdumpCommand, SetLoggingCommand, ShowHeapdumpCommand, ShowLoggingCommand, SimpleRedirectorCommand, WhatisCommand, XCommand

public abstract class BaseJdmpviewCommand
extends BaseCommand

This the base command for all jdmpview commands. It ensures consistent behaviour with the legacy commands without breaking the generic command encapsulation. There are a number of methods which allow DTFJ objects to be consistently displayed across different plugins e.g. getClassInfo(). Where the method name starts with getXYZ the output will be returned for further processing, however where the method starts with writeXYZ then the output is written immediately to the command's print stream.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static class	BaseJdmpviewCommand.ArtifactType	Enum for identifying the type of artifact that is currently being analyzed.

Field Summary

Fields

Modifier and Type	Field	Description
protected IDTFJContext	ctx
protected String	hexfmt
protected Logger	logger
protected PrintStream	out

Fields declared in class com.ibm.java.diagnostics.utils.commands.BaseCommand

COMMAND_FORMAT, config, nl, SUBCOMMAND_FORMAT

Constructor Summary

Constructors

Constructor	Description
BaseJdmpviewCommand()

Method Summary

Modifier and Type	Method	Description
String	decodeThreadState(int state)	Textual description of a thread state.
protected BaseJdmpviewCommand.ArtifactType	getArtifactType()	Determine the type of artifact currently being operated on.
String	handleException(Throwable cause)	Lots of DTFJ methods will throw a standard set of exceptions such as corrupt data or data unavailable.
boolean	initCommand(String command, String[] args, IContext context, PrintStream out)	Common processing to initialize the command and make the porting of existing jdmpview commands easier.
abstract void	printDetailedHelp(PrintStream out)	Print detailed help for a given command
String	toHexString(byte num)	Format a number with the correct number of zeros as padding according to the data type passed in.
String	toHexString(int num)	Format a number with the correct number of zeros as padding according to the data type passed in.
String	toHexString(long num)	Format a number with the correct number of zeros as padding according to the data type passed in.
String	toHexString(short num)	Format a number with the correct number of zeros as padding according to the data type passed in.
String	toHexStringAddr(long num)	Format an address as hex padded with zeros according to the size of the process.
long	toLong(String number)	Typically used when an extension takes a numeric argument, and wants to accept a variety of formats.
String	toString(double num)	Convenience method to convert a number into a String to display.
String	toString(float num)	Convenience method to convert a number into a String to display.

Methods declared in class com.ibm.java.diagnostics.utils.commands.BaseCommand

addCommand, addSubCommand, setConfig

Methods declared in class java.lang.Object

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

Methods declared in interface com.ibm.java.diagnostics.utils.commands.ICommand

getCommandDescriptions, getCommandNames, getConfig, recognises, run

Field Detail

out

protected PrintStream out

ctx

protected IDTFJContext ctx

logger

protected Logger logger

hexfmt

protected String hexfmt

Constructor Detail

BaseJdmpviewCommand

public BaseJdmpviewCommand()

Method Detail

printDetailedHelp

public abstract void printDetailedHelp(PrintStream out)

Print detailed help for a given command

Parameters:

out - stream to write the output to

initCommand

public final boolean initCommand(String command,
                                 String[] args,
                                 IContext context,
                                 PrintStream out)
                          throws CommandException

Common processing to initialize the command and make the porting of existing jdmpview commands easier.

Parameters:

command - the command being executed

args - the supplied arguments

context - the context within which it is operating

out - where to write the output

Returns:

returns true if this method has handled the output and the subclass should exit

Throws:

CommandException

toLong

public long toLong(String number)

Typically used when an extension takes a numeric argument, and wants to accept a variety of formats. Currently it will support decimal or hexadecimal formats.

Parameters:

number - String representation of the number to parse

Returns:

the numeric value

getArtifactType

protected BaseJdmpviewCommand.ArtifactType getArtifactType()

Determine the type of artifact currently being operated on.

Returns:

artifact type

toHexStringAddr

public String toHexStringAddr(long num)

Format an address as hex padded with zeros according to the size of the process. e.g. 17 would be formatted as 0x00000011 for 32 bit and 0x0000000000000011 for 64 bit

Parameters:

num - the number to format

Returns:

formatted number

handleException

public String handleException(Throwable cause)

Lots of DTFJ methods will throw a standard set of exceptions such as corrupt data or data unavailable. This method provides a central point for handling these exceptions and attempts to provide more context as to whether or not this is an expected occurrence for the artifact type under analysis.

Parameters:

cause - the exception returned from a call to the DTFJ API

Returns:

formatted string for displaying to the user

decodeThreadState

public String decodeThreadState(int state)

Textual description of a thread state.

Parameters:

state - state to convert

Returns:

cumulative description of the states

toHexString

public String toHexString(long num)

Format a number with the correct number of zeros as padding according to the data type passed in.

Parameters:

num - the number to format

Returns:

formatted number

toHexString

public String toHexString(short num)

Format a number with the correct number of zeros as padding according to the data type passed in.

Parameters:

num - the number to format

Returns:

formatted number

toHexString

public String toHexString(int num)

Format a number with the correct number of zeros as padding according to the data type passed in.

Parameters:

num - the number to format

Returns:

formatted number

toHexString

public String toHexString(byte num)

Format a number with the correct number of zeros as padding according to the data type passed in.

Parameters:

num - the number to format

Returns:

formatted number

toString

public String toString(float num)

Convenience method to convert a number into a String to display.

Parameters:

num - the number to format

Returns:

formatted number

toString

public String toString(double num)

Convenience method to convert a number into a String to display.

Parameters:

num - the number to format

Returns:

formatted number