Javadoc Task

## Javadoc/Javadoc2

Deprecation: the `javadoc2` task simply points to the `javadoc` task and it's there for backwards compatibility reasons. Since this task will be removed in future versions, you are strongly encouraged to use javadoc instead.

### Description

Generates code documentation using the `javadoc` tool.

The source directory will be recursively scanned for Java source files to process but only those matching the inclusion rules, and not matching the exclusions rules will be passed to the `javadoc` tool. This allows wildcards to be used to choose between package names, reducing verbosity and management costs over time. This task, however, has no notion of "changed" files, unlike the javac task. This means all packages will be processed each time this task is run. In general, however, this task is used much less frequently.

Note: since `javadoc` calls `System.exit()`, `javadoc` cannot be run inside the same JVM as Apache Ant without breaking functionality. For this reason, this task always forks JVM. This overhead is not significant since `javadoc` is normally a heavy application and will be called infrequently.

Note: the packagelist attribute allows you to specify the list of packages to document outside of the Ant file. It's a much better practice to include everything inside the `build.xml` file. This option was added in order to make it easier to migrate from regular makefiles, where you would use this option of `javadoc`. The packages listed in packagelist are not checked, so the task performs even if some packages are missing or broken. Use this option if you wish to convert from an existing makefile. Once things are running you should then switch to the regular notation.

In the table below, 1.2 means available if your current JVM is exactly of version 1.2 (not 1.3 or later), 1.4+ for any JVM of at least version 1.4, otherwise any JVM of at least version 1.2 is acceptable. JDKs prior to 1.4 are no longer supported. If you specify the executable attribute it is up to you to ensure that this command supports the attributes you wish to use.

Note: When generating the JavaDocs for classes which contains annotations you maybe get a `java.lang.ClassCastException: com.sun.tools.javadoc.ClassDocImpl`. This is due bug 6442982. The cause is that `javadoc` cannot find the implementations of used annotations. The workaround is providing the jars with these implementations (like JAXBs `@XmlType`, ...) to `<javadoc>` using classpath, classpathref attributes or nested `<classpath>` element.

Note: many problems with running `javadoc` stem from command lines that have become too long—even though the error message doesn't give the slightest hint this may be the problem. If you encounter problems with the task, try to set the useexternalfile attribute to true first.

If you use multiple ways to specify where `javadoc` should be looking for sources, your result will be the union of all specified documentations. If you, e.g., specify a sourcepath attribute and also a nested `packageset` both pointing at the same directory your excludepackagenames attribute won't have any effect unless it agrees with the exclude patterns of the `packageset` (and vice versa).

### Parameters

Attribute | Description | Availability on Java | Required
--- | --- | --- | ---
sourcepath | Specify where to find source files | all | At least one of the three or nested `<sourcepath>`, `<fileset>` or `<packageset>`
sourcepathref | Specify where to find source files by reference to a sourcepath defined elsewhere. | all
sourcefiles | Comma separated list of source files—see also the nested `source` element. | all
destdir | Destination directory for output files | all | Yes, unless a doclet has been specified.
maxmemory | Max amount of memory to allocate to the `javadoc` JVM | all | No
packagenames | Comma separated list of package files (with terminating wildcard)—see also the nested `package` element. | all | No
packageList | The name of a file containing the packages to process | all | No
classpath | Specify where to find user class files | all | No
Bootclasspath | Override location of class files loaded by the bootstrap class loader | all | No
classpathref | Specify where to find user class files by reference to a classpath defined elsewhere. | all | No
bootclasspathref | Override location of class files loaded by the bootstrap class loader by reference to a bootclasspath defined elsewhere. | all | No
Extdirs | Override location of installed extensions | all | No
Overview | Read overview documentation from HTML file | all | No
access | Access mode: one of public, protected, package, or private | all | No; default is protected
Public | Show only public classes and members | all | No
Protected | Show protected/public classes and members (default) | all | No
Package | Show package/protected/public classes and members | all | No
Private | Show all classes and members | all | No
Old | Generate output using JDK 1.1 emulating doclet. Note: Since Ant 1.8.0 this attribute has no effect because `javadoc` of Java 1.4 and later does not support the `-1.1` switch anymore. | 1.2 | No
Verbose | Output messages about what `javadoc` is doing | all | No
Locale | Locale to be used, e.g. en_US or en_US_WIN | all | No
Encoding | Source file encoding name | all | No
Version | Include `@version` paragraphs | all | No
Use | Create class and package usage pages | all | No
Author | Include `@author` paragraphs | all | No
Splitindex | Split index into one file per letter | all | No
Windowtitle | Browser window title for the documentation (text) | all | No
Doctitle | Include title for the package index (first) page (HTML code) | all | No
Header | Include header text for each page (HTML code) | all | No
Footer | Include footer text for each page (HTML code) | all | No
bottom | Include bottom text for each page (HTML code) | all | No
link | Create links to `javadoc` output at the given URL—see also the nested `link` element. | all | No
linkoffline | Link to docs at `url` using package list at `alt-url` by specifying a value url alt-url (space as separator). A shorthand for the nested `link` element with offline=true. | all | No
group | Group specified packages together in overview page. The format is as described below—see also the nested `group` element. | all | No
nodeprecated | Do not include `@deprecated` information | all | No
nodeprecatedlist | Do not generate deprecated list | all | No
notree | Do not generate class hierarchy | all | No
noindex | Do not generate index | all | No
nohelp | Do not generate help link | all | No
nonavbar | Do not generate navigation bar | all | No
serialwarn | Generate warning about `@serial` tag | all | No
helpfile | Specifies the HTML help file to use | all | No
stylesheetfile | Specifies the CSS stylesheet to use | all | No
charset | Charset for cross-platform viewing of generated documentation | all | No
docencoding | Output file encoding name | all | No
doclet | Specifies the class file that starts the doclet used in generating the documentation—see also the nested `doclet` element. | all | No
docletpath | Specifies the path to the doclet class file that is specified with the `-doclet` option. | all | No
docletpathref | Specifies the path to the doclet class file that is specified with the `-doclet` option by reference to a path defined elsewhere. | all | No
additionalparam | Lets you add additional parameters to the `javadoc` command line. Useful for doclets. Parameters containing spaces need to be quoted using &quot;—see also the nested `arg` element. | all | No
failonerror | Stop the build process if the command exits with a return code other than 0. | all | No
failonwarning | Stop the build process if a warning is emitted—i.e. if `javadoc`'s output contains the word warning. since Ant 1.9.4 | all | No
excludepackagenames | comma separated list of packages you don't want docs for—see also the nested `excludepackage` element. | all | No
defaultexcludes | indicates whether default excludes should be used (yes|no). | all | No; defaults to yes
useexternalfile | indicates whether the source file names specified in srcfiles or as nested `source` elements should be written to a temporary file to make the command line shorter. Also applies to the package names specified via the packagenames attribute or nested `package` elements. Since Ant 1.7.0, also applies to all the other command line options. (yes|no). | all | No; default is no
source | Enable `javadoc` to handle Java language features. Set this to 1.4 to document code that compiles using `javac -source 1.4`, etc. | 1.4+ | No; default can be provided using the magic `ant.build.javac.source` property.
linksource | Generate hyperlinks to source files. since Ant 1.6. (yes|no). | 1.4+ | No; default is no
breakiterator | Use the new break iterator algorithm. since Ant 1.6. (yes|no). | 1.4+ | No; default is no
noqualifier | Enables the `-noqualifier` argument—must be all or a colon separated list of packages. since Ant 1.6. | 1.4+ | No
includenosourcepackages | If set to true, packages that don't contain Java source but a `package.html` will get documented as well. since Ant 1.6.3. | all | No; default is false
executable | Specify a particular `javadoc` executable to use in place of the default binary (found in the same JDK as Ant is running in). since Ant 1.6.3. | all | No
docfilessubdirs | Enables deep-copying of `doc-files` subdirectories. since Ant 1.8.0. | 1.4 | No; defaults to false
excludedocfilessubdir | Colon-separated list of `doc-files` subdirectories to exclude if docfilessubdirs is true. since Ant 1.8.0. | 1.4 | No
postProcessGeneratedJavadocs | Whether to post-process the generated javadocs in order to mitigate CVE-2013-1571. Since Ant 1.9.2 There is a frame injection attack possible in javadocs generated by Oracle JDKs prior to Java 7 update 25 (details). When this flag is set to true, Ant will check whether the docs are vulnerable and will try to fix them. | 1.4 | No; defaults to true

#### Format of the group attribute

The arguments are comma-delimited. Each single argument is 2 space-delimited strings, where the first one is the group's title and the second one a colon delimited list of packages.

If you need to specify more than one group, or a group whose title contains a comma or a space character, using nested `group` elements is highly recommended.

E.g.:

    group="XSLT_Packages org.apache.xalan.xslt*,XPath_Packages org.apache.xalan.xpath*"

### Parameters specified as nested elements

#### packageset

A DirSet. All matched directories that contain Java source files will be passed to `javadoc` as package names. Package names are created from the directory names by translating the directory separator into dots. Ant assumes the base directory of the `packageset` points to the root of a package hierarchy.

The packagenames, excludepackagenames and defaultexcludes attributes of the task have no effect on the nested `<packageset>` elements.

#### fileset

A FileSet. All matched files will be passed to `javadoc` as source files. Ant will automatically add the include pattern `**/*.java` (and `**/package.html` if includenosourcepackages is true) to these filesets.

Nested filesets can be used to document sources that are in the default package or if you want to exclude certain files from documentation. If you want to document all source files and don't use the default package, `packageset`s should be used instead as this increases performance of `javadoc`.

The packagenames, excludepackagenames and defaultexcludes attributes of the task have no effect on the nested `<fileset>` elements.

#### sourcefiles

A container for arbitrary file system based resource collections. All files contained in any of the nested collections (this includes nested filesets, filelists or paths) will be passed to javadoc as source files.

#### package

Same as one entry in the list given by packagenames.

##### Parameters

Attribute | Description | Required
--- | --- | ---
name | The package name (may be a wildcard) | Yes

#### excludepackage

Same as one entry in the list given by excludepackagenames.

##### Parameters

Same as for `package`.

#### source

Same as one entry in the list given by sourcefiles.

##### Parameters

Attribute | Description | Required
--- | --- | ---
file | The source file to document | Yes

#### doctitle

Same as the doctitle attribute, but you can nest text inside the element this way.

If the nested text contains line breaks, you must use the useexternalfile attribute and set it to true.

#### header

Similar to `<doctitle>`.

#### footer

Similar to `<doctitle>`.

#### bottom

Similar to `<doctitle>`.

#### link

Create link to `javadoc` output at the given URL. This performs the same role as the link and linkoffline attributes. You can use either syntax (or both at once), but with the nested elements you can easily specify multiple occurrences of the arguments.

##### Parameters

Attribute | Description | Required
--- | --- | ---
href | The URL for the external documentation you wish to link to. This can be an absolute URL, or a relative file name. | Yes
offline | true if this link is not available online at the time of generating the documentation | No
packagelistLoc | The location to the directory containing the package-list file for the external documentation | One of the two if the offline attribute is true
packagelistURL | The URL of the the directory containing the package-list file for the external documentation
resolveLink | If the link attribute is a relative file name, Ant will first try to locate the file relative to the current project's basedir and if it finds a file there use an absolute URL for the link attribute, otherwise it will pass the file name verbatim to the `javadoc` command. | No; default is false

#### group

Separates packages on the overview page into whatever groups you specify, one group per table. This performs the same role as the group attribute. You can use either syntax (or both at once), but with the nested elements you can easily specify multiple occurrences of the arguments.

##### Parameters

Attribute | Description | Required
--- | --- | ---
title | Title of the group | Yes, unless nested `<title>` given
packages | List of packages to include in that group. Multiple packages are separated with :. | Yes, unless nested `<package>`s given

The title may be specified as a nested `<title>` element with text contents, and the packages may be listed with nested `<package>` elements as for the main task.

#### doclet

The doclet nested element is used to specify the doclet that `javadoc` will use to process the input source files. A number of the standard `javadoc` arguments are actually arguments of the standard doclet. If these are specified in the `javadoc` task's attributes, they will be passed to the doclet specified in the `<doclet>` nested element. Such attributes should only be specified, therefore, if they can be interpreted by the doclet in use.

If the doclet requires additional parameters, these can be specified with `<param>` elements within the `<doclet>` element. These parameters are restricted to simple strings. An example usage of the `doclet` element is shown below:

    <javadoc ... >
       <doclet name="theDoclet"
               path="path/to/theDoclet">
          <param name="-foo" value="foovalue"/>
          <param name="-bar" value="barvalue"/>
       </doclet>
    </javadoc>

#### tag

If you want to specify a standard tag using a nested `tag` element because you want to determine the order the tags are output, you must not set the description attribute for those tags.

##### Parameters

Attribute | Description | Required
--- | --- | ---
name | Name of the tag (e.g. todo) | Yes, unless the dir attribute is specified
description | Description for tag (e.g. To do:) | No, the `javadoc` executable will pick a default if this is not specified
enabled | Whether or not the tag is enabled | No; defaults to true
scope | Scope for the tag—the elements in which it can be used. This is a comma separated list of some of the elements: overview, packages, types, constructors, methods, fields or the default, all. | No; defaults to all
dir | If this attribute is specified, this element will behave as an implicit fileset. The files included by this fileset should contain each tag definition on a separate line, as described in the Javadoc reference guide:
    ejb.bean:t:XDoclet EJB Tag
    todo:a:To Do
Note: The Javadoc reference quide has double quotes around the description part of the definition. This will not work when used in a file, as the definition is quoted again when given to the `javadoc` program. Note: If this attribute is specified, all the other attributes in this element will be ignored. | No

#### taglet

The taglet nested element is used to specify custom taglets beyond the default taglets.

##### Parameters

Attribute | Description | Required
--- | --- | ---
name | The name of the taglet class (e.g. `com.sun.tools.doclets.ToDoTaglet`) | Yes
path | A path specifying the search path for the taglet class (e.g. `/home/taglets`). The path may also be specified by a nested `<path>` element | No

#### sourcepath, classpath and bootclasspath

`Javadoc`'s sourcepath, classpath and bootclasspath attributes are path-like structure and can also be set via nested `sourcepath`, `classpath` and `bootclasspath` elements respectively.

#### arg

Since Ant 1.6

Use nested `<arg>` to specify additional arguments. See Command line arguments.

### Example

    <javadoc packagenames="com.dummy.test.*"
             sourcepath="src"
             excludepackagenames="com.dummy.test.doc-files.*"
             defaultexcludes="yes"
             destdir="docs/api"
             author="true"
             version="true"
             use="true"
             windowtitle="Test API">
      <doctitle><![CDATA[<h1>Test</h1>]]></doctitle>
      <bottom><![CDATA[<i>Copyright &#169; 2000 Dummy Corp. All Rights Reserved.</i>]]></bottom>
      <tag name="todo" scope="all" description="To do:"/>
      <group title="Group 1 Packages" packages="com.dummy.test.a*"/>
      <group title="Group 2 Packages" packages="com.dummy.test.b*:com.dummy.test.c*"/>
      <link offline="true" href="https://docs.oracle.com/javase/8/docs/api/" packagelistLoc="C:\tmp"/>
      <link href="https://docs.oracle.com/javase/8/docs/api/"/>
    </javadoc>

is the same as

    <javadoc destdir="docs/api"
             author="true"
             version="true"
             use="true"
             windowtitle="Test API">

      <packageset dir="src" defaultexcludes="yes">
        <include name="com/dummy/test/**"/>
        <exclude name="com/dummy/test/doc-files/**"/>
      </packageset>

      <doctitle><![CDATA[<h1>Test</h1>]]></doctitle>
      <bottom><![CDATA[<i>Copyright &#169; 2000 Dummy Corp. All Rights Reserved.</i>]]></bottom>
      <tag name="todo" scope="all" description="To do:"/>
      <group title="Group 1 Packages" packages="com.dummy.test.a*"/>
      <group title="Group 2 Packages" packages="com.dummy.test.b*:com.dummy.test.c*"/>
      <link offline="true" href="https://docs.oracle.com/javase/8/docs/api/" packagelistLoc="C:\tmp"/>
      <link href="https://docs.oracle.com/javase/8/docs/api/"/>
    </javadoc>

or

    <javadoc destdir="docs/api"
             author="true"
             version="true"
             use="true"
             windowtitle="Test API">

      <fileset dir="src" defaultexcludes="yes">
        <include name="com/dummy/test/**"/>
        <exclude name="com/dummy/test/doc-files/**"/>
      </fileset>

      <doctitle><![CDATA[<h1>Test</h1>]]></doctitle>
      <bottom><![CDATA[<i>Copyright &#169; 2000 Dummy Corp. All Rights Reserved.</i>]]></bottom>
      <tag name="todo" scope="all" description="To do:"/>
      <group title="Group 1 Packages" packages="com.dummy.test.a*"/>
      <group title="Group 2 Packages" packages="com.dummy.test.b*:com.dummy.test.c*"/>
      <link offline="true" href="https://docs.oracle.com/javase/8/docs/api/" packagelistLoc="C:\tmp"/>
      <link href="https://docs.oracle.com/javase/8/docs/api/"/>
    </javadoc>