| <!-- javac task --> |
| <external> |
| <description> |
| |
| <p>Compiles a Java source tree.</p> |
| |
| <p>The source and destination directory will be recursively scanned for Java |
| source files to compile. Only Java files that have no corresponding class file |
| or where the class file is older than the java file will be compiled.</p> |
| |
| <p>Note: Ant uses only the names of the source and class files to find |
| the classes that need a rebuild. It will not scan the source and therefor |
| will have no knowledge about nested classes, classes that are named different |
| from the source file and so on.</p> |
| |
| <p>The directory structure of the source tree should follow the package |
| hierarchy.</p> |
| |
| <p>It is possible to refine the set of files that are being compiled/copied. |
| This can be done with the <i>includes</i>, <i>includesfile</i>, <i>excludes</i>, <i>excludesfile</i> and <i>defaultexcludes</i> |
| attributes. With the <i>includes</i> or <i>includesfile</i> attribute you specify the files you want to |
| have included by using patterns. The <i>exclude</i> or <i>excludesfile</i> attribute is used to specify |
| the files you want to have excluded. This is also done with patterns. And |
| finally with the <i>defaultexcludes</i> attribute, you can specify whether you |
| want to use default exclusions or not. See the section on <a |
| href="../dirtasks.html#directorybasedtasks">directory based tasks</a>, on how the |
| inclusion/exclusion of files works, and how to write patterns.</p> |
| |
| <p>It is possible to use different compilers. This can be selected with the |
| "build.compiler" property or the compiler attribute. Here are the choices:-</p> |
| <ul> |
| <li>classic (the standard compiler of JDK 1.1/1.2) - javac1.1 and |
| javac1.2 can be used as aliases</li> |
| <li>modern (the standard compiler of JDK 1.3/1.4) - javac1.3 and |
| javac1.4 can be used as aliases</li> |
| <li>jikes (the <a |
| href="http://oss.software.ibm.com/developerworks/opensource/jikes/project" target="_top">Jikes</a> |
| compiler)</li> |
| <li>jvc (the Command-Line Compiler from Microsoft's SDK for Java / |
| Visual J++) - microsoft can be used as an alias</li> |
| <li>kjc (the <a href="http://www.dms.at/kopi/" target="_top">kopi</a> |
| compiler)</li> |
| <li>gcj (the gcj compiler from gcc)</li> |
| <li>sj (Symantec java compiler) - symantec can be used as an alias</li> |
| <li>extJavac (run either modern or classic in a JVM of its own)</li> |
| </ul> |
| <p>For JDK 1.1/1.2, classic is the default. For JDK 1.3/1.4, modern is the default. |
| If you wish to use a different compiler interface than those |
| supplied, write a class that implements the CompilerAdapter interface |
| (package org.apache.tools.ant.taskdefs.compilers). Supply the full |
| classname in the "build.compiler" property.</p> |
| |
| <p>The fork attribute overrides the build.compiler setting and expects |
| a JDK1.1 or higher to be set in java.home.</p> |
| |
| <p>This task will drop all entries that point to non-existent |
| files/directories from the CLASSPATH it passes to the compiler.</p> |
| |
| <p><strong>Windows Note:</strong>When the modern compiler is used |
| in unforked mode on Windows, it locks up the files present in the |
| classpath of the <javac> task, and does not release them. The side |
| effect of this is that you will not be able to delete or move |
| those files later on in the build. The workaround is to fork when |
| invoking the compiler.</p> |
| |
| </description> |
| |
| <section anchor="examples" name="Examples"> |
| <pre> <javac srcdir="${src}" |
| destdir="${build}" |
| classpath="xyz.jar" |
| debug="on" |
| /></pre> |
| <p>compiles all <code>.java</code> files under the <code>${src}</code> |
| directory, and stores |
| the <code>.class</code> files in the <code>${build}</code> directory. |
| The classpath used contains <code>xyz.jar</code>, and debug information is on.</p> |
| |
| <pre> <javac srcdir="${src}" |
| destdir="${build}" |
| fork="true" |
| /></pre> |
| <p>compiles all <code>.java</code> files under the <code>${src}</code> |
| directory, and stores the <code>.class</code> files in the |
| <code>${build}</code> directory. This will fork off the javac |
| compiler using the default javac executable.</p> |
| |
| <pre> <javac srcdir="${src}" |
| destdir="${build}" |
| fork="java$$javac.exe" |
| /></pre> |
| <p>compiles all <code>.java</code> files under the <code>${src}</code> |
| directory, and stores the <code>.class</code> files in the |
| <code>${build}</code> directory. This will fork off the javac |
| compiler using the executable named <code>java$javac.exe</code>. Note |
| that the <code>$</code> sign needs to be escaped by a second one.</p> |
| |
| <pre> <javac srcdir="${src}" |
| destdir="${build}" |
| includes="mypackage/p1/**,mypackage/p2/**" |
| excludes="mypackage/p1/testpackage/**" |
| classpath="xyz.jar" |
| debug="on" |
| /></pre> |
| <p>compiles <code>.java</code> files under the <code>${src}</code> |
| directory, and stores the |
| <code>.class</code> files in the <code>${build}</code> directory. |
| The classpath used contains <code>xyz.jar</code>, and debug information is on. |
| Only files under <code>mypackage/p1</code> and <code>mypackage/p2</code> are |
| used. Files in the <code>mypackage/p1/testpackage</code> directory are excluded |
| from compilation.</p> |
| |
| <pre> <javac srcdir="${src}:${src2}" |
| destdir="${build}" |
| includes="mypackage/p1/**,mypackage/p2/**" |
| excludes="mypackage/p1/testpackage/**" |
| classpath="xyz.jar" |
| debug="on" |
| /></pre> |
| |
| <p>is the same as the previous example, with the addition of a second |
| source path, defined by |
| the property <code>src2</code>. This can also be represented using nested |
| <code><src></code> elements as follows:</p> |
| |
| <pre> <javac destdir="${build}" |
| classpath="xyz.jar" |
| debug="on"> |
| <src path="${src}"/> |
| <src path="${src2}"/> |
| <include name="mypackage/p1/**"/> |
| <include name="mypackage/p2/**"/> |
| <exclude name="mypackage/p1/testpackage/**"/> |
| </javac></pre> |
| |
| <p><b>Note:</b> If you are using Ant on Windows and a new DOS window pops up |
| for every use of an external compiler, this may be a problem of the JDK you are using. |
| This problem may occur with all JDKs < 1.2.</p> |
| |
| <p><b>Note:</b> If you wish to compile only source-files located in some packages below a |
| common root you should not include these packages in the srcdir-attribute. Use include/exclude-attributes |
| or elements to filter for these packages. If you include part of your package-structure inside the srcdir-attribute |
| (or nested src-elements) Ant will start to recompile your sources every time you call it.</p> |
| |
| </section> |
| |
| <section anchor="jikes" name="Jikes Notes"> |
| |
| <p>Jikes supports some extra options, which can be set be defining |
| properties prior to invoking the task. The ant developers are aware that |
| this is ugly and inflexible -expect a better solution in the future. All |
| the options are boolean, and must be set to "true" or "yes" to be |
| interpreted as anything other than false; by default |
| build.compiler.warnings is "true" while all others are "false"</p> |
| |
| <table border="1" cellpadding="2" cellspacing="0"> |
| <tr> |
| <td valign="top"> |
| build.compiler.emacs |
| </td> |
| <td valign="top"> |
| Enable emacs compatible error messages |
| </td> |
| </tr> |
| <tr> |
| <td valign="top"> |
| build.compiler.warnings<br /> |
| <b>This property has been deprecated, use the nowarn attribute |
| instead</b> |
| </td> |
| <td valign="top"> |
| don't disable warning messages |
| </td> |
| </tr> |
| <tr> |
| <td valign="top"> |
| build.compiler.pedantic |
| </td> |
| <td valign="top"> |
| enable pedantic warnings |
| </td> |
| </tr> |
| <tr> |
| <td valign="top"> |
| build.compiler.fulldepend |
| </td> |
| <td valign="top"> |
| enable full dependency checking,<br /> |
| "+F" in the jikes manual. |
| </td> |
| </tr> |
| </table> |
| |
| </section> |
| </external> |
