B.2.1 build, B.2.1, Build – Sun Microsystems J2ME User Manual

Page 116

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J2ME Wireless Toolkit User’s Guide • October 2004

B.2.1

Build

Using KToolbar, building a project is a single step. Behind the scenes, however,
there are actually two steps. First, Java source files are compiled into Java class
files. Next, the class files are preverified, which means they are prepared for the
CLDC KVM.

Use the

javac

compiler from the J2SE SDK to compile Java source files. You can

use the existing J2ME Wireless Toolkit project directory structure. You’ll need to
use the

-bootclasspath

option to tell the compiler to use the MIDP APIs, and

you’ll use the

-d

option to tell the compiler where to put the compiled class files.

The following example shows how you could compile a MIDP 2.0 application,
taking source files from the

src

directory and placing the class files in the

tmpclasses

directory. Newlines have been added for clarity.

javac

-bootclasspath ..\..\lib\cldcapi10.jar;..\..\lib\midpapi20.jar

-d tmpclasses

src\*.java

If you want to use the optional APIs that are supported by the toolkit, add their
JAR files to the

-bootclasspath

option.

For more information on

javac

, consult the J2SE documentation.

The next step is to preverify the class files. In the

bin

directory of the J2ME

Wireless Toolkit lives a handy utility called

preverify

. The syntax for the

preverify command is as follows:

preverify [

options

] <

files

|

directories

>

Some of the options are as follows:

-classpath

<classpath>

Specify the directories or JAR files (given as a semicolon-delimited list) from
which classes are loaded.

-d

<output directory>

Specify the directory into which the preverifier should output classes. This
directory must exist before preverifying. If this option is not used, the preverifier
places the classes in a directory called output.

Following the example for compiling, use the following command to verify the
compiled class files. As before, newlines have been added for clarity.

preverify

-classpath ..\..\lib\cldcapi10.jar;..\..\lib\midpapi20.jar

-d classes

tmpclasses

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