org.jacorb.util

Class ObjectUtil

java.lang.Object

org.jacorb.util.ObjectUtil

public final class ObjectUtil
extends Object

Author:

Gerald Brose, FU Berlin

Method Summary

Methods

Modifier and Type	Method and Description
static void	appendHex(StringBuffer buffer, int value)
static Properties	argsToProps(String[] args) Convenience method to parse an argument vector (typically from the command line) and sets any arguments of the form "-Dy=x" as values in a properties object.
static String	bufToString(byte[] values, int start, int len)
static Class<?>	classForName(String name) Returns the Class object for the class or interface with the given string name.
static URL	getResource(String name)
static String	readURL(String url)
static char	toAscii(byte value)
static String	toHex(byte value) toHex converts a byte into a readable string.

Methods inherited from class java.lang.Object

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

Method Detail

readURL

public static String readURL(String url)
                      throws IOException

Returns:

the contents of the resource as a string, or null if the contents of the resource could not be located using url

Throws:

IOException

classForName

public static Class<?> classForName(String name)
                             throws ClassNotFoundException,
                                    IllegalArgumentException

Returns the Class object for the class or interface with the given string name. This method is a replacement for Class.forName(String name). Unlike Class.forName(String name) (which always uses the caller's loader or one of its ancestors), classForName uses a thread-specific loader that has no delegation relationship with the caller's loader. It attempts the load the desired class with the thread-specific context class loader and falls back to Class.forName(String name) only if the context class loader cannot load the class.

Loading a class with a loader that is not necessarily an ancestor of the caller's loader is a crucial thing in many scenarios. As an example, assume that JacORB was loaded by the boot class loader, and suppose that some code in JacORB contains a call Class.forName(someUserClass). Such usage of Class.forName effectively forces the user to place someUserClass in the boot class path. If classForName(someUserClass) were used instead, the user class would be loaded by the context class loader, which by default is set to the system (CLASSPATH) classloader.

In this simple example above, the default setting of the context class loader allows classes in the boot classpath to reach classes in the system classpath. In other scenarios, the context class loader might be different from the system classloader. Middleware systems like servlet containers or EJB containers set the context class loader so that a given thread can reach user-provided classes that are not in the system classpath.

For maximum flexibility, classForName should replace Class.forName(String name) in nearly all cases.

Parameters:

name - the fully qualified name of a class

Returns:

the Class object for that class

Throws:

IllegalArgumentException - if name is null

ClassNotFoundException - if the named class cannot be found

LinkageError - if the linkage fails

ExceptionInInitializerError - if the class initialization fails

bufToString

public static String bufToString(byte[] values,
                 int start,
                 int len)

appendHex

public static void appendHex(StringBuffer buffer,
             int value)

toHex

public static String toHex(byte value)

toHex converts a byte into a readable string.

Parameters:

value - a byte value

Returns:

a String value

toAscii

public static char toAscii(byte value)

argsToProps

public static Properties argsToProps(String[] args)

Convenience method to parse an argument vector (typically from the command line) and sets any arguments of the form "-Dy=x" as values in a properties object.

getResource

public static URL getResource(String name)