JPad is Java editor that runs on Windows ® 95 and Windows NT platforms. In terms of other ModelWorks products, JPad is a subset of JPad Pro that provides a basic capability to edit, compile and run Java programs. Note that printing is enabled only in a registered version.
The following figure shows a screen shot of JPad. The upper panel is where you edit Java files. The bottom panel is the output panel which is where output is displayed from tools.
Java support in JPad is currently based upon Sun's Java Development Kit (JDK). JDK itself is just a collection of command line tools and related files. JPad provides a set of commands that make it easy to use the JDK tools. For example, to compile a Java class you just have to open a Java file and then choose the "Compile" command from the Java menu. By contrast, to use JDK directly you have to type in a command line with the correct parameters, copy down information about any errors, and then go back to your editor to correct the errors. JPad does this and more in one environment.
To use the Java tools, first open or create a java file and then choose a Java tool. For example, to compile the file HelloWorld.java, open the file HelloWorld.java and then choose "Compile" from the Java menu. The figure below shows the result of compiling a program with an error where the word "system" should be spelled "System".
To locate an error all you need to do is to double click on a error message that includes a line number. You can also turn on JPad's line number option or use the "Go To " command if you want to locate the error yourself.
When JPad is installed it sets up a default configuration that
can be used for building small projects such as an applet or simple
Java application. However the default installation does not set
up access to on-line Java documentation nor does it set up access
to your HTML browser. To set these features up, open the Configure
dialog, shown below, and enter the paths to your on-line documentation
and to your browser. You can use the browse buttons located to
the right of the text field to locate these paths. For the Java
help files we recommend that you download the "Dippy Bird
Java Documentation" from http://www.dippybird.com.
You can also use the Configure dialog to configure JPad's Java tools. For example, to configure the Run command, select Run from the list of tools and choose Edit.. or just double click the tool. This will bring up the Run command dialog shown below. Using this dialog you can enter custom options for java.exe (see your java.exe manual page for the list of available options) and can enter any parameters to be passed to your application. If necessary you can also change the tool path. The other tools can be configured in a similar manner.
One other important areas of configuring Java tools is the classpath. JDK tools need to know where to look in your system for Java class files. JDK tools use either the environment variable CLASSPATHS or the "classpaths" command line argument. JPad uses the classpaths command line argument when invoking JDK tools rather than relying on the CLASSPATHS environment variable.
The list of paths passed in the classpaths command line argument to JDK tools is shown in the Classpaths dialog (see below). There should always be at least one entry in this list to the \java\lib\classes.zip file. This file is a ziped file of all the class files distributed with JDK. Without this entry you will get class not found errors when you try to compile a java file. If you are trying to build a Java package then you will also need to add an entry to the folder containing your package in the Classpaths dialog.
Send comments, suggestions or bug reports to Chet Murphy at cmurphy@modelworks.com. If you got this release from a CD-ROM distribution be sure to check out ModelWorks for latest release and for information about other ModelWorks products..
Copyright (c) 1996, Modelworks Software. All rights reserved.
JPad and JPad Pro are a trademarks of ModelWorks Software. Java is a trademark of Sun Microsystems, Inc. Windows is a registered trademark of Microsoft Corporation.