JspmBrowserLauncher

Overview

Package

Class

Use

Deprecated

Index

Home >> All >> com >> [ gui overview ]

PREV CLASS NEXT CLASS

SUMMARY:

JAVADOC |

Sourc code of com.gui.JspmBrowserLauncher

SOURCE |

DOWNLOAD | NESTED | FIELD | CONSTR | METHOD

DETAIL: FIELD | CONSTR | METHOD

com.gui
Class JspmBrowserLauncher

java.lang.Object
  com.gui.JspmBrowserLauncher

public class JspmBrowserLauncher
extends java.lang.Object

BrowserLauncher is a class that provides one static method, openURL, which opens the default web browser for the current user of the system to the given URL. It may support other protocols depending on the system -- mailto, ftp, etc. -- but that has not been rigorously tested and is not guaranteed to work.

Yes, this is platform-specific code, and yes, it may rely on classes on certain platforms that are not part of the standard JDK. What we're trying to do, though, is to take something that's frequently desirable but inherently platform-specific -- opening a default browser -- and allow programmers (you, for example) to do so without worrying about dropping into native code or doing anything else similarly evil.

Anyway, this code is completely in Java and will run on all JDK 1.1-compliant systems without modification or a need for additional libraries. All classes that are required on certain platforms to allow this to run are dynamically loaded at runtime via reflection and, if not found, will not cause this to do anything other than returning an error when opening the browser.

There are certain system requirements for this class, as it's running through Runtime.exec(), which is Java's way of making a native system call. Currently, this requires that a Macintosh have a Finder which supports the GURL event, which is true for Mac OS 8.0 and 8.1 systems that have the Internet Scripting AppleScript dictionary installed in the Scripting Additions folder in the Extensions folder (which is installed by default as far as I know under Mac OS 8.0 and 8.1), and for all Mac OS 8.5 and later systems. On Windows, it only runs under Win32 systems (Windows 95, 98, and NT 4.0, as well as later versions of all). On other systems, this drops back from the inherently platform-sensitive concept of a default browser and simply attempts to launch Netscape via a shell command.

This code is Copyright 1999 by Eric Albert (ejalbert@cs.stanford.edu) and may be redistributed or modified in any form without restrictions as long as the portion of this comment from this paragraph through the end of the comment is not removed. The author requests that he be notified of any application, applet, or other binary that makes use of this code, but that's more out of curiosity than anything and is not required. This software includes no warranty.

Credits:
Steven Spencer, JavaWorld magazine (Java Tip 66)
Ron B. Yeh, ZeroG
Ben Engber, The New York Times
Paul Teitlebaum and Andrea Cantatore, Datatech Software

Version:: 1.2 (Released July 28, 1999)

Field Summary

private static java.lang.Class aeDescClass
          The com.apple.MacOS.AEDesc class

private static java.lang.reflect.Constructor aeDescConstructor
          The (String) method of com.apple.MacOS.AEDesc

private static java.lang.reflect.Constructor aeTargetConstructor
          The (int) method of com.apple.MacOS.AETarget

private static java.lang.reflect.Constructor appleEventConstructor
          The (int, int, int) method of com.apple.MacOS.AppleEvent

private static java.lang.Object browser
          The browser for the system

private static java.lang.String errorMessage
          The message from any exception thrown throughout the initialization process.

private static java.lang.String FINDER_CREATOR
          The creator code of the Finder on a Macintosh, which is needed to send AppleEvents to the application.

private static java.lang.String FINDER_TYPE
          The file type of the Finder on a Macintosh.

private static java.lang.reflect.Method findFolder
          The findFolder method of com.apple.mrj.MRJFileUtils

private static java.lang.String FIRST_WINDOWS_PARAMETER
          The first parameter that needs to be passed into Runtime.exec() to open the default web browser on Windows.

private static java.lang.reflect.Method getFileType
          The getFileType method of com.apple.mrj.MRJOSType

private static java.lang.String GURL_EVENT
          The name for the AppleEvent type corresponding to a GetURL event.

private static int jvm
          The Java virtual machine that we are running on.

private static java.lang.Integer kAnyTransactionID
          The kAnyTransactionID AppleEvent code

private static java.lang.Integer kAutoGenerateReturnID
          The kAutoGenerateReturnID AppleEvent code

private static java.lang.Integer keyDirectObject
          The keyDirectObject AppleEvent parameter type

private static java.lang.Object kSystemFolderType
          Actually an MRJOSType pointing to the System Folder on a Macintosh

private static boolean loadedWithoutErrors
          Caches whether any classes, methods, and fields that are not part of the JDK and need to be dynamically loaded at runtime loaded successfully.

private static java.lang.Class macOSErrorClass
          The com.apple.MacOS.MacOSError class

private static java.lang.reflect.Method makeOSType
          The makeOSType method of com.apple.MacOS.OSUtils

private static int MRJ_2_0
          JVM constant for MRJ 2.0

private static int MRJ_2_1
          JVM constant for MRJ 2.1 or later

private static java.lang.Class mrjFileUtilsClass
          The com.apple.mrj.MRJFileUtils class

private static java.lang.Class mrjOSTypeClass
          The com.apple.mrj.MRJOSType class

private static java.lang.String NETSCAPE_OPEN_PARAMETER_END


private static java.lang.String NETSCAPE_OPEN_PARAMETER_START
          The shell parameters for Netscape that opens a given URL in an already-open copy of Netscape on many command-line systems.

private static int OTHER
          JVM constant for any other platform

private static java.lang.reflect.Method putParameter
          The putParameter method of com.apple.MacOS.AppleEvent

private static java.lang.String SECOND_WINDOWS_PARAMETER
          The second parameter for Runtime.exec() on Windows.

private static java.lang.reflect.Method sendNoReply
          The sendNoReply method of com.apple.MacOS.AppleEvent

private static int WINDOWS_9x
          JVM constant for any Windows 9x JVM

private static int WINDOWS_NT
          JVM constant for any Windows NT JVM

Constructor Summary

private JspmBrowserLauncher()
          This class should be never be instantiated; this just ensures so.

Method Summary

private static boolean loadClasses()
          Called by a static initializer to load any classes, fields, and methods required at runtime to locate the user's web browser.

private static java.lang.Object locateBrowser()
          Attempts to locate the default web browser on the local system.

static void openURL(java.lang.String url)
          Attempts to open the default web browser to the given URL.

Methods inherited from class java.lang.Object

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

Field Detail

jvm

private static int jvm

The Java virtual machine that we are running on. Actually, in most cases we only care about the operating system, but some operating systems require us to switch on the VM.

browser

private static java.lang.Object browser

The browser for the system

loadedWithoutErrors

private static boolean loadedWithoutErrors

Caches whether any classes, methods, and fields that are not part of the JDK and need to be dynamically loaded at runtime loaded successfully.

Note that if this is false, openURL() will always return an IOException.

mrjFileUtilsClass

private static java.lang.Class mrjFileUtilsClass

The com.apple.mrj.MRJFileUtils class

mrjOSTypeClass

private static java.lang.Class mrjOSTypeClass

The com.apple.mrj.MRJOSType class

macOSErrorClass

private static java.lang.Class macOSErrorClass

The com.apple.MacOS.MacOSError class

aeDescClass

private static java.lang.Class aeDescClass

The com.apple.MacOS.AEDesc class

aeTargetConstructor

private static java.lang.reflect.Constructor aeTargetConstructor

The (int) method of com.apple.MacOS.AETarget

appleEventConstructor

private static java.lang.reflect.Constructor appleEventConstructor

The (int, int, int) method of com.apple.MacOS.AppleEvent

aeDescConstructor

private static java.lang.reflect.Constructor aeDescConstructor

The (String) method of com.apple.MacOS.AEDesc

findFolder

private static java.lang.reflect.Method findFolder

The findFolder method of com.apple.mrj.MRJFileUtils

getFileType

private static java.lang.reflect.Method getFileType

The getFileType method of com.apple.mrj.MRJOSType

makeOSType

private static java.lang.reflect.Method makeOSType

The makeOSType method of com.apple.MacOS.OSUtils

putParameter

private static java.lang.reflect.Method putParameter

The putParameter method of com.apple.MacOS.AppleEvent

sendNoReply

private static java.lang.reflect.Method sendNoReply

The sendNoReply method of com.apple.MacOS.AppleEvent

kSystemFolderType

private static java.lang.Object kSystemFolderType

Actually an MRJOSType pointing to the System Folder on a Macintosh

keyDirectObject

private static java.lang.Integer keyDirectObject

The keyDirectObject AppleEvent parameter type

kAutoGenerateReturnID

private static java.lang.Integer kAutoGenerateReturnID

The kAutoGenerateReturnID AppleEvent code

kAnyTransactionID

private static java.lang.Integer kAnyTransactionID

The kAnyTransactionID AppleEvent code

MRJ_2_0

private static final int MRJ_2_0

JVM constant for MRJ 2.0

See Also:: Constant Field Values

MRJ_2_1

private static final int MRJ_2_1

JVM constant for MRJ 2.1 or later

See Also:: Constant Field Values

WINDOWS_NT

private static final int WINDOWS_NT

JVM constant for any Windows NT JVM

See Also:: Constant Field Values

WINDOWS_9x

private static final int WINDOWS_9x

JVM constant for any Windows 9x JVM

See Also:: Constant Field Values

OTHER

private static final int OTHER

JVM constant for any other platform

See Also:: Constant Field Values

FINDER_TYPE

private static final java.lang.String FINDER_TYPE

The file type of the Finder on a Macintosh. Hardcoding "Finder" would keep non-U.S. English systems from working properly.

See Also:: Constant Field Values

FINDER_CREATOR

private static final java.lang.String FINDER_CREATOR

The creator code of the Finder on a Macintosh, which is needed to send AppleEvents to the application.

See Also:: Constant Field Values

GURL_EVENT

private static final java.lang.String GURL_EVENT

The name for the AppleEvent type corresponding to a GetURL event.

See Also:: Constant Field Values

FIRST_WINDOWS_PARAMETER

private static final java.lang.String FIRST_WINDOWS_PARAMETER

The first parameter that needs to be passed into Runtime.exec() to open the default web browser on Windows.

See Also:: Constant Field Values

SECOND_WINDOWS_PARAMETER

private static final java.lang.String SECOND_WINDOWS_PARAMETER

The second parameter for Runtime.exec() on Windows.

See Also:: Constant Field Values

NETSCAPE_OPEN_PARAMETER_START

private static final java.lang.String NETSCAPE_OPEN_PARAMETER_START

The shell parameters for Netscape that opens a given URL in an already-open copy of Netscape on many command-line systems.

See Also:: Constant Field Values

NETSCAPE_OPEN_PARAMETER_END

private static final java.lang.String NETSCAPE_OPEN_PARAMETER_END

See Also:: Constant Field Values

errorMessage

private static java.lang.String errorMessage

The message from any exception thrown throughout the initialization process.

Constructor Detail