JAVADOC(1) JDK Commands JAVADOC(1)
NAME
javadoc - generate HTML pages of API documentation from Java source
files
SYNOPSIS
javadoc [options] [packagenames] [sourcefiles] [@files]
options
Specifies command-line options, separated by spaces. See Stan-
dard javadoc Options, Extra javadoc Options, Standard Options
for the Standard Doclet, and Extra Options for the Standard Do-
clet.
packagenames
Specifies names of packages that you want to document, separated
by spaces, for example java.lang java.lang.reflect java.awt. If
you want to also document the subpackages, then use the -sub-
packages option to specify the packages.
By default, javadoc looks for the specified packages in the cur-
rent directory and subdirectories. Use the -sourcepath option
to specify the list of directories where to look for packages.
sourcefiles
Specifies names of Java source files that you want to document,
separated by spaces, for example Class.java Object.java But-
ton.java. By default, javadoc looks for the specified classes
in the current directory. However, you can specify the full
path to the class file and use wildcard characters, for example
/home/src/java/awt/Graphics*.java. You can also specify the
path relative to the current directory.
@files Specifies names of files that contain a list of javadoc tool op-
tions, package names, and source file names in any order.
DESCRIPTION
The javadoc tool parses the declarations and documentation comments in
a set of Java source files and produces corresponding HTML pages that
describe (by default) the public and protected classes, nested and un-
named classes (but not anonymous inner classes), interfaces, construc-
tors, methods, and fields. You can use thejavadoc tool to generate the
API documentation or the implementation documentation for a set of
source files.
You can run the javadoc tool on entire packages, individual source
files, or both. When documenting entire packages, you can use the
-subpackages option either to recursively traverse a directory and its
subdirectories, or to pass in an explicit list of package names. When
you document individual source files, pass in a list of Java source
file names.
Conformance
The Standard Doclet does not validate the content of documentation com-
ments for conformance, nor does it attempt to correct any errors in
documentation comments. Anyone running javadoc is advised to be aware
of the problems that may arise when generating non-conformant output or
output containing executable content, such as JavaScript. The Standard
Doclet does provide the DocLint feature to help developers detect com-
mon problems in documentation comments; but it is also recommended to
check the generated output with any appropriate conformance and other
checking tools.
For more details on the conformance requirements for HTML5 documents,
see Conformance requirements [https://www.w3.org/TR/html5/infrastruc-
ture.html#conformance-requirements] in the HTML5 Specification. For
more details on security issues related to web pages, see the Open Web
Application Security Project (OWASP) [https://www.owasp.org] page.
OPTIONS
javadoc supports command-line options for both the main javadoc tool
and the currently selected doclet. The Standard Doclet is used if no
other doclet is specified.
GNU-style options (that is, those beginning with --) can use an equal
sign (=) instead of whitespace characters to separate the name of an
option from its value.
Standard javadoc Options
The following core javadoc options are equivalent to corresponding
javac options. See Standard Options in javac for the detailed descrip-
tions of using these options:
• --add-modules
• -bootclasspath
• --class-path, -classpath, or -cp
• --enable-preview
• -encoding
• -extdirs
• --limit-modules
• --module
• --module-path or -p
• --module-source-path
• --release
• --source or -source
• --source-path or -sourcepath
• --system
• --upgrade-module-path
The following options are the core javadoc options that are not equiva-
lent to a corresponding javac option:
-breakiterator
Computes the first sentence with BreakIterator. The first sen-
tence is copied to the package, class, or member summary and to
the alphabetic index. The BreakIterator class is used to deter-
mine the end of a sentence for all languages except for English.
• English default sentence-break algorithm --- Stops at a period
followed by a space or an HTML block tag, such as <P>.
• Breakiterator sentence-break algorithm --- Stops at a period,
question mark, or exclamation point followed by a space when
the next word starts with a capital letter. This is meant to
handle most abbreviations (such as "The serial no. is valid",
but will not handle "Mr. Smith"). The -breakiterator option
doesn't stop at HTML tags or sentences that begin with numbers
or symbols. The algorithm stops at the last period in
../filename, even when embedded in an HTML tag.
-doclet class
Generates output by using an alternate doclet. Use the fully
qualified name. This doclet defines the content and formats the
output. If the -doclet option isn't used, then the javadoc tool
uses the standard doclet for generating the default HTML format.
This class must contain the start(Root) method. The path to
this starting class is defined by the -docletpath option.
-docletpath path
Specifies where to find doclet class files (specified with the
-doclet option) and any JAR files it depends on. If the start-
ing class file is in a JAR file, then this option specifies the
path to that JAR file. You can specify an absolute path or a
path relative to the current directory. If classpathlist con-
tains multiple paths or JAR files, then they should be separated
with a colon (:) on Linux and a semi-colon (;) on Windows. This
option isn't necessary when the doclet starting class is already
in the search path.
-exclude pkglist
Unconditionally, excludes the specified packages and their sub-
packages from the list formed by -subpackages. It excludes
those packages even when they would otherwise be included by
some earlier or later -subpackages option.
The following example would include java.io, java.util, and ja-
va.math (among others), but would exclude packages rooted at ja-
va.net and java.lang. Notice that these examples exclude ja-
va.lang.ref, which is a subpackage of java.lang.
• Linux and macOS:
javadoc -sourcepath /home/user/src -subpackages java -exclude java.net:java.lang
• Windows:
javadoc -sourcepath \user\src -subpackages java -exclude java.net:java.lang
--expand-requires value
Instructs the javadoc tool to expand the set of modules to be
documented. By default, only the modules given explicitly on
the command line are documented. Supports the following values:
• transitive: additionally includes all the required transitive
dependencies of those modules.
• all: includes all dependencies.
--help, -help, -h, or -?
Prints a synopsis of the standard options.
--help-extra or -X
Prints a synopsis of the set of extra options.
-Jflag Passes flag directly to the Java Runtime Environment (JRE) that
runs the javadoc tool. For example, if you must ensure that the
system sets aside 32 MB of memory in which to process the gener-
ated documentation, then you would call the -Xmx option as fol-
lows: javadoc -J-Xmx32m -J-Xms32m com.mypackage. Be aware that
-Xms is optional because it only sets the size of initial memo-
ry, which is useful when you know the minimum amount of memory
required.
There is no space between the J and the flag.
Use the -version option to report the version of the JRE being
used to run the javadoc tool.
javadoc -J-version
java version "17" 2021-09-14 LTS
Java(TM) SE Runtime Environment (build 17+35-LTS-2724)
Java HotSpot(TM) 64-Bit Server VM (build 17+35-LTS-2724, mixed mode, sharing)
-locale name
Specifies the locale that the javadoc tool uses when it gener-
ates documentation. The argument is the name of the locale, as
described in java.util.Locale documentation, such as en_US (Eng-
lish, United States) or en_US_WIN (Windows variant).
Specifying a locale causes the javadoc tool to choose the re-
source files of that locale for messages such as strings in the
navigation bar, headings for lists and tables, help file con-
tents, comments in the stylesheet.css file, and so on. It also
specifies the sorting order for lists sorted alphabetically, and
the sentence separator to determine the end of the first sen-
tence. The -locale option doesn't determine the locale of the
documentation comment text specified in the source files of the
documented classes.
-package
Shows only package, protected, and public classes and members.
-private
Shows all classes and members.
-protected
Shows only protected and public classes and members. This is
the default.
-public
Shows only the public classes and members.
-quiet Shuts off messages so that only the warnings and errors appear
to make them easier to view. It also suppresses the version
string.
--show-members value
Specifies which members (fields or methods) are documented,
where value can be any of the following:
• public --- shows only public members
• protected --- shows public and protected members; this is the
default
• package --- shows public, protected, and package members
• private --- shows all members
--show-module-contents value
Specifies the documentation granularity of module declarations,
where value can be api or all.
--show-packages value
Specifies which modules packages are documented, where value can
be exported or all packages.
--show-types value
Specifies which types (classes, interfaces, etc.) are document-
ed, where value can be any of the following:
• public --- shows only public types
• protected --- shows public and protected types; this is the
default
• package --- shows public, protected, and package types
• private --- shows all types
-subpackages subpkglist
Generates documentation from source files in the specified pack-
ages and recursively in their subpackages. This option is use-
ful when adding new subpackages to the source code because they
are automatically included. Each package argument is any top-
level subpackage (such as java) or fully qualified package (such
as javax.swing) that doesn't need to contain source files. Ar-
guments are separated by colons on all operating systems. Wild
cards aren't allowed. Use -sourcepath to specify where to find
the packages. This option doesn't process source files that are
in the source tree but don't belong to the packages.
For example, the following commands generates documentation for
packages named java and javax.swing and all of their subpack-
ages.
• Linux and macOS:
javadoc -d docs -sourcepath /home/user/src -subpackages java:javax.swing
• Windows:
javadoc -d docs -sourcepath \user\src -subpackages java:javax.swing
-verbose
Provides more detailed messages while the javadoc tool runs.
Without the -verbose option, messages appear for loading the
source files, generating the documentation (one message per
source file), and sorting. The -verbose option causes the
printing of additional messages that specify the number of mil-
liseconds to parse each Java source file.
--version
Prints version information.
-Werror
Reports an error if any warnings occur.
Extra javadoc Options
Note: The additional options for javadoc are subject to change without
notice.
The following additional javadoc options are equivalent to correspond-
ing javac options. See Extra Options in javac for the detailed de-
scriptions of using these options:
• --add-exports
• --add-reads
• --patch-module
• -Xmaxerrs
• -Xmaxwarns
Standard Options for the Standard Doclet
The following options are provided by the standard doclet.
--add-script file
Adds file as an additional JavaScript file to the generated doc-
umentation. This option can be used one or more times to speci-
fy additional script files.
Command-line example:
javadoc --add-script first_script.js --add-script sec-
ond_script.js pkg_foo
--add-stylesheet file
Adds file as an additional stylesheet file to the generated doc-
umentation. This option can be used one or more times to speci-
fy additional stylesheets included in the documentation.
Command-line example:
javadoc --add-stylesheet new_stylesheet_1.css --add-stylesheet new_stylesheet_2.css pkg_foo
--allow-script-in-comments
Allow JavaScript in options and comments.
-author
Includes the @author text in the generated docs.
-bottom html-code
Specifies the text to be placed at the bottom of each output
file. The text is placed at the bottom of the page, underneath
the lower navigation bar. The text can contain HTML tags and
white space, but when it does, the text must be enclosed in quo-
tation marks. Use escape characters for any internal quotation
marks within text.
-charset name
Specifies the HTML character set for this document. The name
should be a preferred MIME name as specified in the IANA Reg-
istry, Character Sets [http://www.iana.org/assignments/charac-
ter-sets].
For example:
javadoc -charset "iso-8859-1" mypackage
This command inserts the following line in the head of every
generated page:
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
The meta tag is described in the HTML standard (4197265 and
4137321), HTML Document Representation
[http://www.w3.org/TR/REC-html40/charset.html#h-5.2.2].
-d directory
Specifies the destination directory where the javadoc tool saves
the generated HTML files. If you omit the -d option, then the
files are saved to the current directory. The directory value
can be absolute or relative to the current working directory.
The destination directory is automatically created when the
javadoc tool runs.
• Linux and macOS: For example, the following command generates
the documentation for the package com.mypackage and saves the
results in the /user/doc/ directory:
javadoc -d /user/doc/ com.mypackage
• Windows: For example, the following command generates the doc-
umentation for the package com.mypackage and saves the results
in the \user\doc\ directory:
javadoc -d \user\doc\ com.mypackage
-docencoding name
Specifies the encoding of the generated HTML files. The name
should be a preferred MIME name as specified in the IANA Reg-
istry, Character Sets [http://www.iana.org/assignments/charac-
ter-sets].
Three options are available for use in a javadoc encoding com-
mand. The -encoding option is used for encoding the files read
by the javadoc tool, while the -docencoding and -charset options
are used for encoding the files written by the tool. Of the
three available options, at most, only the input and an output
encoding option are used in a single encoding command. If you
specify both input and output encoding options in a command,
they must be the same value. If you specify neither output op-
tion, it defaults to the input encoding.
For example:
javadoc -docencoding "iso-8859-1" mypackage
-docfilessubdirs
Recursively copies doc-file subdirectories. Enables deep copy-
ing of doc-files directories. Subdirectories and all contents
are recursively copied to the destination. For example, the di-
rectory doc-files/example/images and all of its contents are
copied. The -excludedocfilessubdir option can be used to ex-
clude specific subdirectories.
-doctitle html-code
Specifies the title to place near the top of the overview summa-
ry file. The text specified in the title tag is placed as a
centered, level-one heading directly beneath the top navigation
bar. The title tag can contain HTML tags and white space, but
when it does, you must enclose the title in quotation marks.
Additional quotation marks within the title tag must be escaped.
For example, javadoc -doctitle "<b>My Library</b><br>v1.0"
com.mypackage.
-excludedocfilessubdir name1,name2...
Excludes any subdirectories with the given names when recursive-
ly copying doc-file subdirectories. See -docfilessubdirs. For
historical reasons, : can be used anywhere in the argument as a
separator instead of ,.
-footer html-code
Specifies the footer text to be placed at the bottom of each
output file. Thehtml-code value is placed to the right of the
lower navigation bar. The html-code value can contain HTML tags
and white space, but when it does, the html-code value must be
enclosed in quotation marks. Use escape characters for any in-
ternal quotation marks within a footer.
-group name p1,p2...
Group the specified packages together in the Overview page. For
historical reasons, : can be used as a separator anywhere in the
argument instead of ,.
-header html-code
Specifies the header text to be placed at the top of each output
file. The header is placed to the right of the upper navigation
bar. The header can contain HTML tags and white space, but when
it does, the header must be enclosed in quotation marks. Use
escape characters for internal quotation marks within a header.
For example, javadoc -header "<b>My Library</b><br>v1.0" com.my-
package.
-helpfile filename
Includes the file that links to the HELP link in the top and
bottom navigation bars . Without this option, the javadoc tool
creates a help file help-doc.html that is hard-coded in the
javadoc tool. This option lets you override the default. The
filename can be any name and isn't restricted to help-doc.html.
The javadoc tool adjusts the links in the navigation bar accord-
ingly. For example:
• Linux and macOS:
javadoc -helpfile /home/user/myhelp.html java.awt
• Windows:
javadoc -helpfile C:\user\myhelp.html java.awt
-html5 This option is a no-op and is just retained for backwards com-
patibility.
--javafx or -javafx
Enables JavaFX functionality. This option is enabled by default
if the JavaFX library classes are detected on the module path.
-keywords
Adds HTML keyword <meta> tags to the generated file for each
class. These tags can help search engines that look for <meta>
tags find the pages. Most search engines that search the entire
Internet don't look at <meta> tags, because pages can misuse
them. Search engines offered by companies that confine their
searches to their own website can benefit by looking at <meta>
tags. The <meta> tags include the fully qualified name of the
class and the unqualified names of the fields and methods. Con-
structors aren't included because they are identical to the
class name. For example, the class String starts with these
keywords:
<meta name="keywords" content="java.lang.String class">
<meta name="keywords" content="CASE_INSENSITIVE_ORDER">
<meta name="keywords" content="length()">
<meta name="keywords" content="charAt()">
-link url
Creates links to existing javadoc generated documentation of ex-
ternally referenced classes. The url argument is the absolute
or relative URL of the directory that contains the external
javadoc generated documentation. You can specify multiple -link
options in a specified javadoc tool run to link to multiple doc-
uments.
Either a package-list or an element-list file must be in this
url directory (otherwise, use the -linkoffline option).
Note: The package-list and element-list files are generated by
the javadoc tool when generating the API documentation and
should not be modified by the user.
When you use the javadoc tool to document packages, it uses the
package-list file to determine the packages declared in an API.
When you generate API documents for modules, the javadoc tool
uses the element-list file to determine the modules and packages
declared in an API.
The javadoc tool reads the names from the appropriate list file
and then links to the packages or modules at that URL.
When the javadoc tool runs, the url value is copied into the <A
HREF> links that are created. Therefore, url must be the URL to
the directory and not to a file.
You can use an absolute link for url to enable your documents to
link to a document on any web site, or you can use a relative
link to link only to a relative location. If you use a relative
link, then the value you pass in should be the relative path
from the destination directory (specified with the -d option) to
the directory containing the packages being linked to. When you
specify an absolute link, you usually use an HTTP link. Howev-
er, if you want to link to a file system that has no web server,
then you can use a file link. Use a file link only when every-
one who wants to access the generated documentation shares the
same file system. In all cases, and on all operating systems,
use a slash as the separator, whether the URL is absolute or
relative, and https:, http:, or file: as specified in the URL
Memo: Uniform Resource Locators
[http://www.ietf.org/rfc/rfc1738.txt].
-link https://<host>/<directory>/<directory>/.../<name>
-link http://<host>/<directory>/<directory>/.../<name>
-link file://<host>/<directory>/<directory>/.../<name>
-link <directory>/<directory>/.../<name>
--link-modularity-mismatch (warn|info)
Specifies whether external documentation with wrong modularity
(e.g. non-modular documentation for a modular library, or the
reverse case) should be reported as a warning (warn) or just a
message (info). The default behavior is to report a warning.
-linkoffline url1 url2
This option is a variation of the -link option. They both cre-
ate links to javadoc generated documentation for externally ref-
erenced classes. You can specify multiple -linkoffline options
in a specified javadoc tool run.
Use the -linkoffline option when:
• Linking to a document on the web that the javadoc tool can't
access through a web connection
• The package-list or element-list file of the external document
either isn't accessible or doesn't exist at the URL location,
but does exist at a different location and can be specified by
either the package-list or element-list file (typically lo-
cal).
Note: The package-list and element-list files are generated by
the javadoc tool when generating the API documentation and
should not be modified by the user.
If url1 is accessible only on the World Wide Web, then the
-linkoffline option removes the constraint that the javadoc tool
must have a web connection to generate documentation.
Another use of the -linkoffline option is as a work-around to
update documents. After you have run the javadoc tool on a full
set of packages or modules, you can run the javadoc tool again
on a smaller set of changed packages or modules, so that the up-
dated files can be inserted back into the original set.
For example, the -linkoffline option takes two arguments. The
first is for the string to be embedded in the <a href> links,
and the second tells the javadoc tool where to find either the
package-list or element-list file.
The url1 or url2 value is the absolute or relative URL of the
directory that contains the external javadoc generated documen-
tation that you want to link to. When relative, the value
should be the relative path from the destination directory
(specified with the -d option) to the root of the packages being
linked to. See url in the -link option.
--link-platform-properties url
Specifies a properties file used to configure links to platform
documentation.
The url argument is expected to point to a properties file con-
taining one or more entries with the following format, where
<version> is the platform version as passed to the --release or
--source option and <url> is the base URL of the corresponding
platform API documentation:
doclet.platform.docs.<version>=<url>
For instance, a properties file containing URLs for releases 15
to 17 might contain the following lines:
doclet.platform.docs.15=https://example.com/api/15/
doclet.platform.docs.16=https://example.com/api/16/
doclet.platform.docs.17=https://example.com/api/17/
If the properties file does not contain an entry for a particu-
lar release no platform links are generated.
-linksource
Creates an HTML version of each source file (with line numbers)
and adds links to them from the standard HTML documentation.
Links are created for classes, interfaces, constructors, meth-
ods, and fields whose declarations are in a source file. Other-
wise, links aren't created, such as for default constructors and
generated classes.
This option exposes all private implementation details in the
included source files, including private classes, private
fields, and the bodies of private methods, regardless of the
-public, -package, -protected, and -private options. Unless you
also use the -private option, not all private classes or inter-
faces are accessible through links.
Each link appears on the name of the identifier in its declara-
tion. For example, the link to the source code of the Button
class would be on the word Button:
public class Button extends Component implements Accessible
The link to the source code of the getLabel method in the Button
class is on the word getLabel:
public String getLabel()
--main-stylesheet file or -stylesheetfile file
Specifies the path of an alternate stylesheet file that contains
the definitions for the CSS styles used in the generated docu-
mentation. This option lets you override the default. If you
do not specify the option, the javadoc tool will create and use
a default stylesheet. The file name can be any name and isn't
restricted to stylesheet.css. The --main-stylesheet option is
the preferred form.
Command-line example:
javadoc --main-stylesheet main_stylesheet.css pkg_foo
-nocomment
Suppresses the entire comment body, including the main descrip-
tion and all tags, and generate only declarations. This option
lets you reuse source files that were originally intended for a
different purpose so that you can produce skeleton HTML documen-
tation during the early stages of a new project.
-nodeprecated
Prevents the generation of any deprecated API in the documenta-
tion. This does what the -nodeprecatedlist option does, and it
doesn't generate any deprecated API throughout the rest of the
documentation. This is useful when writing code when you don't
want to be distracted by the deprecated code.
-nodeprecatedlist
Prevents the generation of the file that contains the list of
deprecated APIs (deprecated-list.html) and the link in the navi-
gation bar to that page. The javadoc tool continues to generate
the deprecated API throughout the rest of the document. This is
useful when your source code contains no deprecated APIs, and
you want to make the navigation bar cleaner.
-nohelp
Omits the HELP link in the navigation bar at the top of each
page of output.
-noindex
Omits the index from the generated documents. The index is pro-
duced by default.
-nonavbar
Prevents the generation of the navigation bar, header, and foot-
er, that are usually found at the top and bottom of the generat-
ed pages. The -nonavbar option has no effect on the -bottom op-
tion. The -nonavbar option is useful when you are interested
only in the content and have no need for navigation, such as
when you are converting the files to PostScript or PDF for
printing only.
--no-platform-links
Prevents the generation of links to platform documentation.
These links are generated by default.
-noqualifier name1,name2...
Excludes the list of qualifiers from the output. The package
name is removed from places where class or interface names ap-
pear. For historical reasons, : can be used anywhere in the ar-
gument as a separator instead of ,.
The following example omits all package qualifiers: -noqualifier
all.
The following example omits java.lang and java.io package quali-
fiers: -noqualifier java.lang:java.io.
The following example omits package qualifiers starting with ja-
va and com.sun subpackages, but not javax: -noqualifier ja-
va.*:com.sun.*.
Where a package qualifier would appear due to the previous be-
havior, the name can be suitably shortened. This rule is in ef-
fect whether or not the -noqualifier option is used.
-nosince
Omits from the generated documents the Since sections associated
with the @since tags.
-notimestamp
Suppresses the time stamp, which is hidden in an HTML comment in
the generated HTML near the top of each page. The -notimestamp
option is useful when you want to run the javadoc tool on two
source bases and get the differences between diff them, because
it prevents time stamps from causing a diff (which would other-
wise be a diff on every page). The time stamp includes the
javadoc tool release number.
-notree
Omits the class and interface hierarchy pages from the generated
documents. These are the pages you reach using the Tree button
in the navigation bar. The hierarchy is produced by default.
--override-methods (detail|summary)
Documents overridden methods in the detail or summary sections.
The default is detail.
-overview filename
Specifies that the javadoc tool should retrieve the text for the
overview documentation from the source file specified by file-
name and place it on the Overview page (overview-summary.html).
A relative path specified with the file name is relative to the
current working directory.
While you can use any name you want for the filename value and
place it anywhere you want for the path, it is typical to name
it overview.html and place it in the source tree at the directo-
ry that contains the topmost package directories. In this loca-
tion, no path is needed when documenting packages, because the
-sourcepath option points to this file.
• Linux and macOS: For example, if the source tree for the ja-
va.lang package is src/classes/java/lang/, then you could
place the overview file at src/classes/overview.html.
• Windows: For example, if the source tree for the java.lang
package is src\classes\java\lang\, then you could place the
overview file at src\classes\overview.html
The overview page is created only when you pass two or more
package names to the javadoc tool. The title on the overview
page is set by -doctitle.
-serialwarn
Generates compile-time warnings for missing @serial tags. By
default, Javadoc generates no serial warnings. Use this option
to display the serial warnings, which helps to properly document
default serializable fields and writeExternal methods.
--since release(,release)*
Generates documentation for APIs that were added or newly depre-
cated in the specified releases.
If the @since tag in the javadoc comment of an element in the
documented source code matches a release passed as option argu-
ment, information about the element and the release it was added
in is included in a "New API" page.
If the "Deprecated API" page is generated and the since element
of the java.lang.Deprecated annotation of a documented element
matches a release in the option arguments, information about the
release the element was deprecated in is added to the "Deprecat-
ed API" page.
Releases are compared using case-sensitive string comparison.
--since-label text
Specifies the text to use in the heading of the "New API" page.
This may contain information about the releases covered in the
page, e.g. "New API in release 2.0", or "New API since release
1".
--snippet-path snippetpathlist
Specifies the search paths for finding files for external snip-
pets. The snippetpathlist can contain multiple paths by sepa-
rating them with the platform path separator (; on Windows; : on
other platforms.) The Standard Doclet first searches the snip-
pet-files subdirectory in the package containing the snippet,
and then searches all the directories in the given list.
-sourcetab tab-length
Specifies the number of spaces each tab uses in the source.
--spec-base-url url
Specifies the base URL for relative URLs in @spec tags, to be
used when generating links to any external specifications. It
can either be an absolute URL, or a relative URL, in which case
it is evaluated relative to the base directory of the generated
output files. The default value is equivalent to {@doc-
Root}/../specs.
-splitindex
Splits the index file into multiple files, alphabetically, one
file per letter, plus a file for any index entries that start
with non-alphabetical symbols.
-tag name:locations:header
Specifies single argument custom tags. For the javadoc tool to
spell-check tag names, it is important to include a -tag option
for every custom tag that is present in the source code, dis-
abling (with X) those that aren't being output in the current
run. The colon (:) is always the separator. To include a colon
in the tag name, escape it with a backward slash (\). The -tag
option outputs the tag heading, header, in bold, followed on the
next line by the text from its single argument. Similar to any
block tag, the argument text can contain inline tags, which are
also interpreted. The output is similar to standard one-argu-
ment tags, such as the @return and @author tags. Omitting a
header value causes the name to be the heading. locations is a
list of characters specifying the kinds of declarations in which
the tag may be used. The following characters may be used, in
either uppercase or lowercase:
• A: all declarations
• C: constructors
• F: fields
• M: methods
• O: the overview page and other documentation files in doc-
files subdirectories
• P: packages
• S: modules
• T: types (classes and interfaces)
• X: nowhere: the tag is disabled, and will be ignored
The order in which tags are given on the command line will be
used as the order in which the tags appear in the generated out-
put. You can include standard tags in the order given on the
command line by using the -tag option with no locations or head-
er.
-taglet class
Specifies the fully qualified name of the taglet used in gener-
ating the documentation for that tag. Use the fully qualified
name for the class value. This taglet also defines the number
of text arguments that the custom tag has. The taglet accepts
those arguments, processes them, and generates the output.
Taglets are useful for block or inline tags. They can have any
number of arguments and implement custom behavior, such as mak-
ing text bold, formatting bullets, writing out the text to a
file, or starting other processes. Taglets can only determine
where a tag should appear and in what form. All other decisions
are made by the doclet. A taglet can't do things such as remove
a class name from the list of included classes. However, it can
execute side effects, such as printing the tag's text to a file
or triggering another process. Use the -tagletpath option to
specify the path to the taglet. The following example inserts
the To Do taglet after Parameters and ahead of Throws in the
generated pages.
-taglet com.sun.tools.doclets.ToDoTaglet
-tagletpath /home/taglets
-tag return
-tag param
-tag todo
-tag throws
-tag see
Alternately, you can use the -taglet option in place of its -tag
option, but that might be difficult to read.
-tagletpath tagletpathlist
Specifies the search paths for finding taglet class files. The
tagletpathlist can contain multiple paths by separating them
with the platform path separator (; on Windows; : on other plat-
forms.) The javadoc tool searches all subdirectories of the
specified paths.
-top html-code
Specifies the text to be placed at the top of each output file.
-use Creates class and package usage pages. Includes one Use page
for each documented class and package. The page describes what
packages, classes, methods, constructors and fields use any API
of the specified class or package. Given class C, things that
use class C would include subclasses of C, fields declared as C,
methods that return C, and methods and constructors with parame-
ters of type C. For example, you can look at the Use page for
the String type. Because the getName method in the ja-
va.awt.Font class returns type String, the getName method uses
String and so the getName method appears on the Use page for
String. This documents only uses of the API, not the implemen-
tation. When a method uses String in its implementation, but
doesn't take a string as an argument or return a string, that
isn't considered a use of String.To access the generated Use
page, go to the class or package and click the Use link in the
navigation bar.
-version
Includes the version text in the generated docs. This text is
omitted by default. To find out what version of the javadoc
tool you are using, use the -J-version option.
-windowtitle title
Specifies the title to be placed in the HTML <title> tag. The
text specified in the title tag appears in the window title and
in any browser bookmarks (favorite places) that someone creates
for this page. This title should not contain any HTML tags be-
cause a browser will not interpret them correctly. Use escape
characters on any internal quotation marks within the title tag.
If the -windowtitle option is omitted, then the javadoc tool us-
es the value of the -doctitle option for the -windowtitle op-
tion. For example, javadoc -windowtitle "My Library" com.my-
package.
Extra Options for the Standard Doclet
The following are additional options provided by the Standard Doclet
and are subject to change without notice. Additional options are less
commonly used or are otherwise regarded as advanced.
--date date-and-time
Specifies the value to be used to timestamp the generated pages,
in ISO 8601 [https://www.iso.org/iso-8601-date-and-time-for-
mat.html] format. The specified value must be within 10 years
of the current date and time. It is an error to specify both
-notimestamp and --date. Using a specific value means the gen-
erated documentation can be part of a reproducible build
[https://reproducible-builds.org/]. If the option is not given,
the default value is the current date and time. For example:
javadoc --date 2022-02-01T17:41:59-08:00 mypackage
--legal-notices (default|none|directory)
Specifies the location from which to copy legal files to the
generated documentation. If the option is not specified or is
used with the value default, the files are copied from the de-
fault location. If the argument is used with value none, no
files are copied. Every other argument is interpreted as direc-
tory from which to copy the legal files.
--no-frames
This option is a no-op and is just retained for backwards com-
patibility.
-Xdoclint
Enables recommended checks for problems in documentation com-
ments.
By default, the -Xdoclint option is enabled. Disable it with
the option -Xdoclint:none.
For more details, see DocLint.
-Xdoclint:flag,flag,...
Enable or disable specific checks for different kinds of issues
in documentation comments.
Each flag can be one of all, none, or [-]group where group has
one of the following values: accessibility, html, missing, ref-
erence, syntax. For more details on these values, see DocLint
Groups.
When specifying two or more flags, you can either use a single
-Xdoclint:... option, listing all the desired flags, or you can
use multiple options giving one or more flag in each option.
For example, use either of the following commands to check for
the HTML, syntax, and accessibility issues in the file My-
File.java.
javadoc -Xdoclint:html -Xdoclint:syntax -Xdoclint:accessibility MyFile.java
javadoc -Xdoclint:html,syntax,accessibility MyFile.java
The following examples illustrate how to change what DocLint re-
ports:
• -Xdoclint:none --- disables all checks
• -Xdoclint:group --- enables group checks
• -Xdoclint:all --- enables all groups of checks
• -Xdoclint:all,-group --- enables all checks except group
checks
For more details, see DocLint.
-Xdoclint/package:[-]packages
Enables or disables checks in specific packages. packages is a
comma separated list of package specifiers. A package specifier
is either a qualified name of a package or a package name prefix
followed by *, which expands to all subpackages of the given
package. Prefix the package specifier with - to disable checks
for the specified packages.
For more details, see DocLint.
-Xdocrootparent url
Replaces all @docRoot items followed by /.. in documentation
comments with url.
DOCLINT
DocLint provides the ability to check for possible problems in documen-
tation comments. Problems may be reported as warnings or errors, de-
pending on their severity. For example, a missing comment may be bad
style that deserves a warning, but a link to an unknown Java declara-
tion is more serious and deserves an error. Problems are organized in-
to groups, and options can be used to enable or disable messages in one
or more groups. Within the source code, messages in one or more groups
can be suppressed by using @SuppressWarnings annotations.
When invoked from javadoc, by default DocLint checks all comments that
are used in the generated documentation. It thus relies on other com-
mand-line options to determine which declarations, and which corre-
sponding documentation comments will be included. Note: this may mean
that even comments on some private members of serializable classes will
also be checked, if the members need to be documented in the generated
Serialized Forms page.
In contrast, when DocLint is invoked from javac, DocLint solely relies
on the various -Xdoclint... options to determine which documentation
comments to check.
DocLint doesn't attempt to fix invalid input, it just reports it.
Note: DocLint doesn't guarantee the completeness of these checks. In
particular, it isn't a full HTML compliance checker. The goal is to
just report common errors in a convenient manner.
Groups
The checks performed by DocLint are organized into groups. The warn-
ings and errors in each group can be enabled or disabled with command-
line options, or suppressed with @SuppressWarnings annotations.
The groups are as follows:
• accessibility --- Checks for issues related to accessibility. For
example, no alt attribute specified in an <img> element, or no cap-
tion or summary attributes specified in a <table> element.
Issues are reported as errors if a downstream validation tool might
be expected to report an error in the files generated by javadoc.
For reference, see the Web Content Accessibility Guidelines
[https://www.w3.org/WAI/standards-guidelines/wcag/].
• html --- Detects common high-level HTML issues. For example, putting
block elements inside inline elements, or not closing elements that
require an end tag.
Issues are reported as errors if a downstream validation tool might
be expected to report an error in the files generated by javadoc.
For reference, see the HTML Living Standard
[https://html.spec.whatwg.org/multipage/].
• missing --- Checks for missing documentation comments or tags. For
example, a missing comment on a class declaration, or a missing
@param or @return tag in the comment for a method declaration.
Issues related to missing items are typically reported as warnings
because they are unlikely to be reported as errors by downstream val-
idation tools that may be used to check the output generated by
javadoc.
• reference --- Checks for issues relating to the references to Java
API elements from documentation comment tags. For example, the ref-
erence in @see or {@link ...} cannot be found, or a bad name is given
for @param or @throws.
Issues are typically reported as errors because while the issue may
not cause problems in the generated files, the author has likely made
a mistake that will lead to incorrect or unexpected documentation.
• syntax --- Checks for low-level syntactic issues in documentation
comments. For example, unescaped angle brackets (< and >) and amper-
sands (&) and invalid documentation comment tags.
Issues are typically reported as errors because the issues may lead
to incorrect or unexpected documentation.
Suppressing Messages
DocLint checks for and recognizes two strings that may be present in
the arguments for an @SuppressWarnings annotation.
• doclint
• doclint:LIST
where LIST is a comma-separated list of one or more of accessibility,
html, missing, syntax, reference.
The names in LIST are the same group names supported by the command-
line -Xdoclint option for javac and javadoc. (This is the same conven-
tion honored by the javac -Xlint option and the corresponding names
supported by @SuppressWarnings.)
The names in LIST can equivalently be specified in separate arguments
of the annotation. For example, the following are equivalent:
• @SuppressWarnings("doclint:accessibility,missing")
• @SuppressWarnings("doclint:accessibility", "doclint:missing")
When DocLint detects an issue in a documentation comment, it checks for
the presence of @SuppressWarnings on the associated declaration and on
all lexically enclosing declarations. The issue will be ignored if any
such annotation is found containing the simple string doclint or the
longer form doclint:LIST where LIST contains the name of the group for
the issue.
Note: as with other uses of @SuppressWarnings, using the annotation on
a module or package declaration only affects that declaration; it does
not affect the contents of the module or package in other source files.
All messages related to an issue are suppressed by the presence of an
appropriate @SuppressWarnings annotation: this includes errors as well
as warnings.
Note: It is only possible to suppress messages. If an annotation of
@SuppressWarnings("doclint") is given on a top-level declaration, all
DocLint messages for that declaration and any enclosed declarations
will be suppressed; it is not possible to selectively re-enable mes-
sages for issues in enclosed declarations.
Comparison with downstream validation tools
DocLint is a utility built into javac and javadoc that checks the con-
tent of documentation comments, as found in source files. In contrast,
downstream validation tools can be used to validate the output generat-
ed from those documentation comments by javadoc and the Standard Do-
clet.
Although there is some overlap in functionality, the two mechanisms are
different and each has its own strengths and weaknesses.
• Downstream validation tools can check the end result of any generated
documentation, as it will be seen by the end user. This includes
content from all sources, including documentation comments, the Stan-
dard Doclet itself, user-provided taglets, and content supplied via
command-line options. Because such tools are analyzing complete HTML
pages, they can do more complete checks than can DocLint. However,
when a problem is found in the generated pages, it can be harder to
track down exactly where in the build pipeline the problem needs to
be fixed.
• DocLint checks the content of documentation comments, in source
files. This makes it very easy to identify the exact position of any
issues that may be found. DocLint can also detect some semantic er-
rors in documentation comments that downstream tools cannot detect,
such as missing comments, using an @return tag in a method returning
void, or an @param tag describing a non-existent parameter. But by
its nature, DocLint cannot report on problems such as missing links,
or errors in user-provided custom taglets, or problems in the Stan-
dard Doclet itself. It also cannot reliably detect errors in docu-
mentation comments at the boundaries between content in a documenta-
tion comment and content generated by a custom taglet.
JDK 21 2023 JAVADOC(1)
Generated by dwww version 1.15 on Sat Jun 29 02:06:53 CEST 2024.