mae.sss
Class Chooser

java.lang.Object
  mae.sss.Chooser

public class Chooser

extends java.lang.Object

Instance methods simplify class loading from a jar file;
class methods add functionality to SSS, mostly to choose from something

Constructor Summary

Chooser(java.lang.ClassLoader L)
Makes an instance using the ClassLoader L.

Method Summary

java.lang.Class	addJarFile() Adds a jar file selected by the user
java.lang.Class	addJarFile(java.io.File f) Adds a jar file to the ClassLoader and the dialog
java.lang.Class	chooseClass() Returns the class selected by the user in the dialog
static java.io.File	file() Shows standard file chooser
static java.io.File	file(java.lang.String e) Shows standard file chooser, showing the files with a given extension
static void	fonts() Shows a font chooser
static java.awt.Frame[]	frames() An array of active Frames, including hidden ones
static void	gc() Invokes System.gc(), showing time and free memory
static java.lang.ClassLoader	getLoader(java.lang.Object x) Who loaded this Object?
static java.lang.Class	loadClass() Shows standard file chooser to choose a class file.
static java.lang.Class	loadClass(java.net.URL u, java.lang.String name) Most general loading method: loads any class anywhere, if its URL is known.
java.lang.ClassLoader	loader() Returns the ClassLoader associated with this Chooser
static Chooser	makeChooser() Chooses a jar file and makes a Chooser with it using a new Loader object; returns null if a jar file is not chosen
static java.lang.Class	systemClass() Shows a dialog to choose a java class (classes that begin with java and javax can be chosen).
static java.lang.Class	systemClass(java.lang.String name) Chooses system class by name (searching java classes, extensions, and the class path)
static java.lang.Thread[]	threads() An array of active Threads

Methods inherited from class java.lang.Object

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

Constructor Detail

Chooser

public Chooser(java.lang.ClassLoader L)

Makes an instance using the ClassLoader L.

All jar files related to L will be scanned and a dialog will be made.

Method Detail

makeChooser

public static Chooser makeChooser()
                           throws java.net.MalformedURLException

Chooses a jar file and makes a Chooser with it using a new Loader object;
returns null if a jar file is not chosen

Throws:

java.net.MalformedURLException

frames

public static java.awt.Frame[] frames()

An array of active Frames, including hidden ones

threads

public static java.lang.Thread[] threads()

An array of active Threads

gc

public static void gc()

Invokes System.gc(), showing time and free memory

file

public static java.io.File file()

Shows standard file chooser

file

public static java.io.File file(java.lang.String e)

Shows standard file chooser, showing the files with a given extension

systemClass

public static java.lang.Class systemClass()
                                   throws java.lang.ClassNotFoundException

Shows a dialog to choose a java class
(classes that begin with java and javax can be chosen).

Throws:

java.lang.ClassNotFoundException

systemClass

public static java.lang.Class systemClass(java.lang.String name)
                                   throws java.lang.ClassNotFoundException

Chooses system class by name
(searching java classes, extensions, and the class path)

Throws:

java.lang.ClassNotFoundException

getLoader

public static java.lang.ClassLoader getLoader(java.lang.Object x)

Who loaded this Object?

loadClass

public static java.lang.Class loadClass()
                                 throws java.lang.ClassNotFoundException

Shows standard file chooser to choose a class file. Choosing a loaded class will load the new version, if modified since last loading

Throws:

java.lang.ClassNotFoundException

loadClass

public static java.lang.Class loadClass(java.net.URL u,
                                        java.lang.String name)
                                 throws java.lang.ClassNotFoundException

Most general loading method: loads any class anywhere, if its URL is known.

Use of loadClass(URL, String)

 1. choose jar File that contains your class
   f = Chooser.file("jar");

 2. get URL of that File object
   u = f.toURL();

 3. press ESC and load your class
   Chooser.loadClass(u, "Hello");
   class Hello
 

How to load a remote class

 1. get URL class (click on java.net and then on URL)
   Chooser.systemClass();
   class java.net.URL

 2. enter URL of a remote Applet (the slash at the end is crucial)
   u2 = new URL("http://java.sun.com/applets/jdk/1.4/demo/applets/ArcTest/");

 3. press ESC and load your class (MAY TAKE SOME TIME)
   Chooser.loadClass(u2, "ArcTest");
   class ArcTest

 4. make an instance
   arc = new ArcTest();

 5. press ESC and show the Applet (you need to resize the Frame)
   Menu.toFrame(arc);
 

Throws:

java.lang.ClassNotFoundException

fonts

public static void fonts()

Shows a font chooser

loader

public java.lang.ClassLoader loader()

Returns the ClassLoader associated with this Chooser

chooseClass

public java.lang.Class chooseClass()
                            throws java.lang.ClassNotFoundException

Returns the class selected by the user in the dialog

Throws:

java.lang.ClassNotFoundException

addJarFile

public java.lang.Class addJarFile()

Adds a jar file selected by the user

addJarFile

public java.lang.Class addJarFile(java.io.File f)

Adds a jar file to the ClassLoader and the dialog