jspc

Description

Ant task to run the JSP compiler and turn JSP pages into Java source.

It can be used to precompile JSP pages for fast initial invocation of JSP pages, deployment on a server without the full JDK installed, or simply to syntax check the pages without deploying them. In most cases, a javac task is usually the next stage in the build process. The task does basic dependency checking to prevent unnecessary recompilation -this checking compares source and destination timestamps, and does not factor in class or taglib dependencies, or <jsp:include> references.

By default the task uses the Jasper JSP compiler. This means the task needs jasper.jar and jasper-runtime.jar, which come with builds of Tomcat 4/Catalina from the Jakarta Tomcat project

Parameters

The Task has the following attributes:

Attribute Description Required

destdir Where to place the generated files. They are located under here according to the given package name. Yes

srcdir Where to look for source jsp files. Yes

verbose The verbosity integer to pass to the compiler. Default="0" No

package Name of the destination package for generated java classes. No

compiler class name of a JSP compiler adapter No

ieplugin Java Plugin classid for Internet Explorer. No

mapped (boolean) Generate separate write() calls for each HTML line in the JSP. No

classpath The classpath to use to run the jsp compiler. This can also be specified by the nested element classpath Path). No

classpathref A Reference. As per classpath No

failonerror flag to control action on compile failures: default=yes No

uribase The uri context of relative URI references in the JSP pages. If it does not exist then it is derived from the location of the file relative to the declared or derived value of uriroot. No

uriroot The root directory that uri files should be resolved against. No

The mapped option will, if set to true, split the JSP text content into a one line per call format. There are comments above and below the mapped write calls to localize where in the JSP file each line of text comes from. This can lead to a minor performance degradation (but it is bound by a linear complexity). Without this options all adjacent writes are concatenated into a single write.

The ieplugin option is used by the <jsp:plugin> tags. If the Java Plug-in COM Class-ID you want to use changes then it can be specified here. This should not need to be altered.

uriroot specifies the root of the web application. This is where all absolute uris will be resolved from. If it is not specified then the first JSP page will be used to derive it. To derive it each parent directory of the first JSP page is searched for a WEB-INF directory, and the directory closest to the JSP page that has one will be used. If none can be found then the directory Jasperc was called from will be used. This only affects pages translated from an explicitly declared JSP file -including references to taglibs

uribase is used to establish the uri context of relative URI references in the JSP pages. If it does not exist then it is derived from the location of the file relative to the declared or derived value of uriroot. This only affects pages translated from an explicitly declared JSP file.

Parameters specified as nested elements

This task is a directory based task, like javac, so the jsp files to be compiled are located as java files are by javac. That is, elements such as includes and excludes can be used directly inside the task declaration.

Elements specific to the jspc task are:-

classpath

The classpath used to compile the JSP pages, specified as for any other classpath.

classpathref

a reference to an existing classpath

webapp

Instructions to jasper to build an entire web application. The base directory must have a WEB-INF subdirectory beneath it. When used, the task hands off all dependency checking to the compiler.

Attribute	Description	Required
basedir	the base directory of the web application	Yes

Example


<jspc srcdir="${basedir}/src/war"

      destdir="${basedir}/gensrc"

      package="com.i3sp.jsp"

      verbose="9">

  <include name="**/*.jsp" />

</jspc>

Build all jsp pages under src/war into the destination /gensrc, in a package heirarchy beginning with com.i3sp.jsp.




<jspc 

      destdir="interim"

      verbose="1"

      srcdir="src"

      package="com.i3sp.jsp">

  <include name="**/*.jsp" />

</jspc>

<depends 

         srcdir="interim"

         destdir="build"

         cache="build/dependencies"

         classpath="lib/taglibs.jar"/>

<javac

         srcdir="interim"

         destdir="build"

         classpath="lib/taglibs.jar"

         debug="on"/>

Generate jsp pages then javac them down to bytecodes. Include lib/taglib jar in the java compilation. Dependency checking is used to scrub the java files if class dependencies indicate it is needed.

Notes

Using the package attribute it is possible to identify the resulting java files and thus do full dependency checking - this task only rebuilds java files if their jsp file has been modified.

Jasper generates JSP pages against the JSP1.3 specification -an implementation of version 2.2 of the servlet specification is needed to compile or run the java code.