org.esa.snap.core.util

Class Debug

java.lang.Object

org.esa.snap.core.util.Debug

Direct Known Subclasses:

JAIDebug

public class Debug
extends Object

The Debug as it name says is a utility class for debugging. It contains exculisvely static methods and cannot be instantiated.

This class provides methods for program assertions as well as tracing capabilities. The tracing output can be redirected to any java.io.XMLCoder. The debbuging capabilities of this class can be disabled at runtime by calling Debug.setEnabled(false).

The methods defined in this class are guaranteed not to throw any exceptions caused by illegal argument passed to them.

Version:

$Revision$ $Date$

See Also:

AssertionFailure

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Debug() Protected constructor.

Method Summary

Modifier and Type	Method and Description
static void	assertNotNull(Object object) If the given object is null, and the debugging functionality is enabled, this method throws an AssertionFailure in order to signal that an internal program post- or pre-condition failed.
static void	assertNotNullOrEmpty(String string) If the given String is null or empty, and the debugging functionality is enabled, this method throws an AssertionFailure in order to signal that an internal program post- or pre-condition failed.
static void	assertTrue(boolean condition) If the condition is NOT true, and the debugging functionality is enabled, this method throws an AssertionFailure in order to signal that an internal program post- or pre-condition failed.
static void	assertTrue(boolean condition, String message) If the condition is NOT true, and the debugging functionality is enabled, this method throws an AssertionFailure in order to signal that an internal program post- or pre-condition failed.
static PrintWriter	getDefaultWriter() Gets the default writer used for debugging output.
static PrintWriter	getWriter() Gets the current writer that will used for debugging output.
static boolean	isEnabled() Checks whether the debugging functionality is enabled or not.
static boolean	isLogging()
protected static void	log(String message) Delegates Debug.trace() calls to the system logger.
protected static void	log(Throwable exception) Delegates Debug.trace() calls to the system logger.
static boolean	setEnabled(boolean enabled) Enables the debugging functionality or disables it.
static void	setLogging(boolean logging)
static void	setWriter(OutputStream stream) Sets the current writer for the given stream that will be used for debugging output.
static void	setWriter(Writer writer) Sets the current writer that will be used for debugging output.
static void	trace(PropertyChangeEvent event) Prints the given property change event to the current writer if and only if the debugging class functionality is enabled.
static void	trace(String message) Prints the given message string to the current writer if and only if the debugging class functionality is enabled.
static void	trace(String name, double[] v)
static void	trace(String name, double[][] v)
static void	trace(Throwable exception) Prints the stack trace for the given exeption to the current writer if and only if the debugging class functionality is enabled.
static void	traceMemoryUsage() Calls traceMemoryUsage(null).
static void	traceMemoryUsage(String label) Prints the ammount of free memory using the given label string to the current writer if and only if the debugging class functionality is enabled.
static void	traceMethodNotImplemented(Class clazz, String methodName) Prints a 'method not implemented' message using the given class and method name string to the current writer if and only if the debugging class functionality is enabled.

Methods inherited from class java.lang.Object

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

Constructor Detail

Debug

protected Debug()

Protected constructor. Used to prevent object instatiation from this class.

Method Detail

isLogging

public static boolean isLogging()

setLogging

public static void setLogging(boolean logging)

setEnabled

public static boolean setEnabled(boolean enabled)

Enables the debugging functionality or disables it.

Parameters:

enabled - if true, debugging functionality will be enabled

isEnabled

public static boolean isEnabled()

Checks whether the debugging functionality is enabled or not.

Returns:

true, if so

getDefaultWriter

public static PrintWriter getDefaultWriter()

Gets the default writer used for debugging output.

Returns:

the default writer, or null if debugging is disabled

getWriter

public static PrintWriter getWriter()

Gets the current writer that will used for debugging output. If no writer was explicitely set by the user, the default writer is returned.

Returns:

the current writer, or null if debugging is disabled

setWriter

public static void setWriter(Writer writer)

Sets the current writer that will be used for debugging output.

Parameters:

writer - the new writer

setWriter

public static void setWriter(OutputStream stream)

Sets the current writer for the given stream that will be used for debugging output.

Parameters:

stream - the stream that will be used for debugging output

trace

public static void trace(String message)

Prints the given message string to the current writer if and only if the debugging class functionality is enabled.

trace

public static void trace(Throwable exception)

Prints the stack trace for the given exeption to the current writer if and only if the debugging class functionality is enabled.

trace

public static void trace(PropertyChangeEvent event)

Prints the given property change event to the current writer if and only if the debugging class functionality is enabled.

traceMemoryUsage

public static void traceMemoryUsage()

Calls traceMemoryUsage(null).

See Also:

traceMemoryUsage(String)

traceMemoryUsage

public static void traceMemoryUsage(String label)

Prints the ammount of free memory using the given label string to the current writer if and only if the debugging class functionality is enabled.

Parameters:

label - an optional label, can be null

traceMethodNotImplemented

public static void traceMethodNotImplemented(Class clazz,
                                             String methodName)

Prints a 'method not implemented' message using the given class and method name string to the current writer if and only if the debugging class functionality is enabled.

Parameters:

clazz - the method's class

methodName - the method's name

assertTrue

public static void assertTrue(boolean condition)
                       throws AssertionFailure

If the condition is NOT true, and the debugging functionality is enabled, this method throws an AssertionFailure in order to signal that an internal program post- or pre-condition failed.

Use this method whenever a valid state must be ensured within your sourcecode in order to safely continue the program.

For example, the method can be used to ensure valid arguments passed to private and protected methods.

Parameters:

condition - the assert condition

Throws:

AssertionFailure - if condition evaluates to false and the debugging functionality is enabled

assertTrue

public static void assertTrue(boolean condition,
                              String message)
                       throws AssertionFailure

If the condition is NOT true, and the debugging functionality is enabled, this method throws an AssertionFailure in order to signal that an internal program post- or pre-condition failed. The AssertionFailure will be created with the given error message string.

Use this method whenever a valid state must be ensured within your sourcecode in order to safely continue the program.

For example, the method can be used to ensure valid arguments passed to private and protected methods.

Parameters:

condition - the assert condition

message - an error message

Throws:

AssertionFailure - if condition evaluates to false and the debugging functionality is enabled

assertNotNull

public static void assertNotNull(Object object)
                          throws AssertionFailure

If the given object is null, and the debugging functionality is enabled, this method throws an AssertionFailure in order to signal that an internal program post- or pre-condition failed.

Use this method whenever a valid state must be ensured within your sourcecode in order to safely continue the program.

For example, the method can be used to ensure valid arguments passed to private and protected methods.

Parameters:

object - the object to test for non-null condition

Throws:

AssertionFailure - if object is null and the debugging functionality is enabled

assertNotNullOrEmpty

public static void assertNotNullOrEmpty(String string)
                                 throws AssertionFailure

If the given String is null or empty, and the debugging functionality is enabled, this method throws an AssertionFailure in order to signal that an internal program post- or pre-condition failed.

Use this method whenever a valid state must be ensured within your sourcecode in order to safely continue the program.

For example, the method can be used to ensure valid arguments passed to private and protected methods.

Parameters:

string - the String to test for non-null and not empty condition

Throws:

AssertionFailure - if String is null or empty and the debugging functionality is enabled

log

protected static void log(String message)

Delegates Debug.trace() calls to the system logger.

Parameters:

message - the message to be logged.

log

protected static void log(Throwable exception)

Delegates Debug.trace() calls to the system logger.

Parameters:

exception - the exception to be logged.

trace

public static void trace(String name,
                         double[][] v)

trace

public static void trace(String name,
                         double[] v)