Packaging:Java

From FedoraProject

(Difference between revisions)
Jump to: navigation, search
(Add category)
(Updated Java Guidelines -- https://fedorahosted.org/fpc/ticket/384)
(10 intermediate revisions by 2 users not shown)
Line 1: Line 1:
 
These guidelines are laid out in order of relevance to packaging.
 
These guidelines are laid out in order of relevance to packaging.
 +
  
 
== Introduction ==
 
== Introduction ==
 +
This page represents Fedora guidelines for packaging libraries and applications written in Java and related languages using Java Virtual Machine as bytecode interpreter. It '''DOES NOT''' aim to extensively describe packaging techniques and tips. RPM macros and commands used here are documented in man pages. Furthermore a separate [https://fedorahosted.org/released/javapackages/doc/ Java Packaging HOWTO] describes Java packaging techniques in detail and includes examples, templates and documentation aimed at packagers and Java developers who are taking their first steps in Java RPM packaging.
  
=== Background ===
+
Fedora Java packaging is originally based on [http://www.jpackage.org JPackage Project] standards. Over time we have diverged in packaging tools in most areas but we mostly keep backward compatibility with older packages that make use of JPackage standards.
Traditionally, Java implementations have been available under a non-free license. Free software clean room implementations of the class library largely centred around GNU Classpath. GCJ, a Java frontend for GCC, allowed for native compilation of Java software. In 2007, Sun released its reference implementation of Java under the GPL+Classpath exception as OpenJDK.  This included the bytecode interpreter, just-in-time (JIT) compiler (Hotspot), and the majority of its class library.  Due to the remaining small proprietary encumbrances, a project known as IcedTea was formed to build OpenJDK with entirely free tools, and provides Free software plugs for the encumbered pieces of the class libraries.  Recent (early 2008) developments have enabled Fedora to ship a package under the OpenJDK name.
+
  
=== The Basics ===
 
The term Java means many things to many people:  a class library, a bytecode interpreter, a JIT compiler, a language specification, etc.  For the vast majority of users and developers, Java is a programming language and runtime environment that is architecture- and OS-agnostic.  The normal flow of code is <code>.java</code> (source file) ’ <code>.class</code> (Java bytecode) ’ <code>.jar</code> (a zip archive).  In the majority of cases, a user executes a Java program by specifying a class name containing a main method (just like C and C++).  Often, this is done by invoking the <code>java</code> binary with a list of JAR files specifying the classpath like so:
 
  
<code>java [-cp <jar1:jar2:jar3>]  <main-class> [<args>] </code>
+
== Package naming ==
  
== Java Packaging ==
+
Packages '''MUST''' follow the standard Fedora [[Packaging/NamingGuidelines | package naming guidelines]].
The [http://www.jpackage.org JPackage Project]  has defined standard file system locations and conventions for use in Java packages.  Many distributions have inherited these conventions and in the vast majority of cases, Fedora follows them verbatim.  We include relevant sections of the JPackage guidelines here but caution that the canonical document will always reside upstream:  [http://www.jpackage.org/cgi-bin/viewvc.cgi/src/jpackage-utils/doc/jpackage-1.5-policy.xhtml?revision=HEAD&root=jpackage JPackage Guidelines] .  Over time, we would like to remove any divergences in these documents, but where they are different, these Fedora guidelines will take precedence for Fedora packages.
+
  
=== Package naming ===
+
Java API documentation '''MUST''' be placed into a sub-package called <code>%{name}-javadoc</code>.
  
Packages '''MUST''' follow the standard Fedora [[Packaging/NamingGuidelines]] .  Java API documentation '''MUST''' be placed into a sub-package called <code>%{name}-javadoc</code>.
+
== Release tags ==
 +
Packages '''MUST''' follow the standard Fedora [[Packaging/NamingGuidelines#Package_Versioning | package versioning guidelines]].
  
==== Release tags ====
+
== Pre-built dependencies ==
For now, refer to the [[Packaging/JPackagePolicy]] for release tags.  That document should eventually be folded into this one.
+
Packages '''MUST''' follow the standard Fedora [[Packaging:Guidelines#No_inclusion_of_pre-built_binaries_or_libraries | dependency bundling guidelines]].
  
=== Jar file naming ===
+
In particular <code>*.class</code> and <code>*.jar</code> files from upstream releases '''MUST NOT''' be used during build of Fedora packages and they '''MUST NOT''' be included in binary RPM.
  
# If a package provides a single JAR file it must have the same name as the package itself.
+
== JAR file installation ==
  
ex. <code>jaf.jar</code>
+
The following applies to all JAR files except [[#JNI|JNI-using JAR files]] and application-specific JAR files (ie. JAR files that can only reasonably be used as part of an application and therefore constitute application-private data).
  
# If the project name and the commonly used JAR filename differ, a symbolic link with the usual name must also be provided.
+
=== Split JAR files ===
  
ex. Single JAR complete naming.  Project name is <code>jaf</code>, common name is <code>activation</code>.
+
If a project offers the choice of packaging it as a single monolithic JAR or several ones, the split packaging '''SHOULD''' be preferred.
  
<code>activation.jar ’ jaf.jar</code>
+
=== Installation directory ===
  
# If the package provides several JAR files, the filenames assigned by the build must be used.  Above symlinking rules apply.
+
* All architecture-independent JAR files '''MUST''' go into <code>%{_javadir}</code> or its subdirectory.
  
ex.   <pre>ant-1.5.3.jar
+
* For installation of architecture dependent JAR files, see [[#Packaging_JAR_files_that_use_JNI|Packaging JAR files that use JNI]].
ant-optional-1.5.3.jar</pre>
+
  
# If the number of provided JAR files exceeds '''two''', you must place them into a sub-directory.
+
=== Filenames ===
  
# If a project offers the choice of packaging it as a single monolithic jar or several ones, the split packaging should be preferred.
+
* If the package provides a '''single''' JAR file installed filename '''SHOULD''' be <code>%{name}.jar</code>.
 +
* If the package provides '''multiple''' JAR file, files '''SHOULD''' be installed in a <code>%{name}</code> subdirectory
 +
* Versioned JAR files (<code>*-%{version}.jar</code>) '''MUST NOT''' be installed unless the package is a compatibility package
 +
* Packages '''CAN''' provide alternative filenames as long as they do not conflict with other packages
  
=== Directory structure ===
 
All JAR files '''MUST''' go into <code>%{_javadir}</code>.  Exceptions include [[JNI|  JNI-using JAR files]] , and application-specific JAR files (ie. JAR files that can only reasonably be used as part of an application and therefore constitute application-private data).
 
  
Java API documentation uses a system known as javadoc.  All javadocs '''MUST''' be installed into <code>%{_javadocdir</code>}.
+
{{admon/note|Note|Here %{name} refers either to package name, or name of subpackage where the jar is installed.}}
  
=== BuildRequires and Requires ===
+
== BuildRequires and Requires ==
At a minimum, Java packages '''MUST''':
+
Java packages '''MUST''' BuildRequire their respective build system:
 +
* <code>BuildRequires: maven-local</code> for packages built with Maven
 +
* <code>BuildRequires: ant</code> for packages built with ant
 +
* <code>BuildRequires: java-devel</code> for packages built with javac
  
<pre>BuildRequires: java-devel [>= specific_version]
+
Java binary packages or their dependencies '''MUST''' have Requires (generated by RPM or manual) on:
BuildRequires: jpackage-utils
+
* <code>java-headless</code> or <code>java-headless >= 1:minimal_required_version</code>
 +
* <code>jpackage-utils</code>
  
Requires: java >= specific_version
+
If java-headless requirement is insufficient package '''MUST''' have Requires:
Requires: jpackage-utils</pre>
+
* <code>java</code> or <code>java >= 1:minimal_required_version</code>
  
For historical reasons, when specifying versions 1.6.0 or greater, an epoch of 1 must be included.  Example:
+
== Javadoc installation ==
  
<pre>Requires: java >= 1:1.6.0
+
* Java API documentation uses a system known as Javadoc.  All javadocs '''MUST''' be created and installed into a directory of <code>%{_javadocdir}/%{name}</code>.  
</pre>
+
* Directory or symlink <code>%{_javadocdir}/%{name}-%{version}</code> '''SHOULD NOT''' exist.
 +
* The javadoc subpackage '''MUST''' be declared <code>noarch</code> even if main package is architecture specific.
  
=== build-classpath ===
+
== No class-path in MANIFEST.MF ==
<code>build-classpath</code> is a script that can be used to generate classpaths from generic names of JAR files. Example:
+
* JAR files '''MUST NOT''' include <code>classh-path</code> entry inside META-INF/MANIFEST.MF
  
<pre>export CLASSPATH=$(build-classpath commons-logging commons-net)
+
== Hardcoded paths ==
</pre>
+
Packages '''MUST NOT''' hardcode paths to JAR files they use.  When package needs to reference a JAR file, packager '''SHOULD''' use one of tools designed to locating JAR files in the system.
  
=== build-jar-repository ===
+
== Maven pom.xml files ==
<code>build-jar-repository</code> is similar to <code>build-classpath</code> but instead of producing a classpath entry, it creates symlinks in a given directory.  Example:
+
If upstream project is shipping Maven <code>pom.xml</code> files, these '''MUST''' be installed. Additionally package '''MUST''' install mapping between upstream artifact and filesystem by using either <code>%mvn_install</code> or <code>%add_maven_depmap</code> macros.
<pre>$ mkdir lib
+
$ build-jar-repository -s -p lib commons-logging commons-net
+
$ ls -l lib
+
commons-logging.jar -> /usr/share/java/commons-logging.jar
+
commons-net.jar -> /usr/share/java/commons-net.jar
+
</pre>
+
  
=== ant ===
+
{{admon/note|Additional documentation|Usage of %add_maven_depmap macro is documented in detail in [https://fedorahosted.org/released/javapackages/doc/#_add_maven_depmap_macro Java Packaging HOWTO].}}
<code>ant</code> is a build tool used by many Java packages.  Packages built using <code>ant</code> ship with <code>build.xml</code> files which contain build targets similar to <code>Makefiles</code>.  Packages built using <code>ant</code> must:
+
  
<pre>BuildRequires: ant
 
...
 
%build
 
...
 
ant
 
</pre>
 
  
=== maven ===
+
If upstream project does not ship Maven <code>pom.xml</code> file, official [http://mvnrepository.com/ maven repository] should be searched and if there are <code>pom.xml</code> files they '''SHOULD''' be installed.
<code>maven</code> is a tool used by many Java packages.  In Fedora, the package is called <code>maven2</code>. Packages built using <code>maven</code> ship with <code>pom.xml</code> files.  They '''MUST''':
+
  
<pre>Requires(post): jpackage-utils
+
If modifications to Maven pom.xml files are needed <code>%pom_*</code> family of macros '''SHOULD''' be used
Requires(postun): jpackage-utils</pre>
+
  
and '''SHOULD''' contain common sections such as the following:
+
{{admon/note|Additional documentation|Usage of %pom_* macros is documented in detail in [https://fedorahosted.org/released/javapackages/doc/#helper_macros Java Packaging HOWTO].}}
  
<pre>
+
== Wrapper Scripts ==
...
+
Applications wishing to provide a convenient method of execution '''SHOULD''' provide a wrapper script in <code>%{_bindir}</code>. Packages '''SHOULD''' use <code>%jpackage_script</code> to create these wrapper scripts.
%build
+
export MAVEN_REPO_LOCAL=$(pwd)/.m2/repository
+
mkdir -p $MAVEN_REPO_LOCAL
+
  
mvn-jpp \
+
{{admon/note|Additional documentation|Usage of %jpackage_script macro is documented in [https://fedorahosted.org/released/javapackages/doc/#_generating_application_shell_scripts Java Packaging HOWTO].}}
-Dmaven.repo.local=$MAVEN_REPO_LOCAL \
+
install javadoc:javadoc
+
...
+
%install
+
rm -rf $RPM_BUILD_ROOT
+
install -d -m 755 $RPM_BUILD_ROOT%{_javadir}
+
install -d -m 755 $RPM_BUILD_ROOT%{_datadir}/maven2/poms
+
install -pm 644 pom.xml $RPM_BUILD_ROOT/%{_datadir}/maven2/poms/JPP-maven-archiver.pom
+
%add_to_maven_depmap org.apache.maven maven-archiver %{version} JPP maven-archiver
+
...
+
%post
+
%update_maven_depmap
+
  
%postun
+
== Compatibility packages ==
%update_maven_depmap
+
In certain cases it might be necessary to create compatibility packages that provide older API/ABI level of the same library. However creating these compatibility packages is strongly discouraged. To standardize and simplify packaging of such compatibility packages following rules apply:
...
+
</pre>
+
  
=== Wrapper Scripts ===
+
* Compatibility packages '''MUST''' be named in the same way as original except addition of version to package name,
Applications wishing to provide a convenient method of execution '''SHOULD''' provide a wrapper script in <code>%{_bindir</code>}.  These can be as simple as this example:
+
* Any JAR and POM files '''MUST''' be versioned.
  
<pre>#!/bin/bash
+
{{admon/note|Ant and Maven compatibility|build-classpath and related tools will resolve versioned jar files if versioned jar is asked for. Maven will use dependency information will return versioned jar if it matches the version asked for in the pom file.}}
. /usr/share/java-utils/java-functions
+
  
MAIN_CLASS=MyCoolApp
+
== Packaging and using EE APIs ==
 +
There are a number of various project providing implementations for Java EE APIs. To simplify packaging and use of these APIs certain standardization is necessary.
  
set_classpath "mycoolapp"
+
=== EE API List ===
 +
Following is a list of EE APIs as of Java EE 6[http://docs.oracle.com/javaee/6/api/] with chosen packages that provide implementations:
 +
* javax.activation - JDK
 +
* javax.annotation - JDK
 +
* javax.el - tomcat-el-2.2-api
 +
* javax.enterprise.inject - cdi-api
 +
* javax.inject - atinject
 +
* javax.jws - JDK
 +
* javax.mail - javamail 
 +
* javax.management - JDK
 +
* javax.management.remote - JDK
 +
* javax.persistence - geronimo-jpa
 +
* javax.security.auth.message - geronimo-jaspic-spec
 +
* javax.servlet - tomcat-servlet-3.0-api
 +
* javax.servlet.jsp - glassfish-jsp/glassfish-jsp-api
 +
* javax.servlet.jsp.jstl - jakarta-taglibs-standard
 +
* javax.transaction - JDK
 +
* javax.ws.rs - jsr-311
 +
* javax.wsdl - wsdl4j
 +
* javax.xml - JDK
 +
* javax.xml.bind - JDK
 +
* javax.xml.rpc - axis
 +
* javax.xml.soap - JDK
 +
* javax.xml.stream - JDK
 +
* javax.xml.ws - JDK
  
run "$@"
+
=== Packages providing APIs ===
</pre>
+
In addition to following generic guidelines they '''MUST''':
 +
* Add '''Provides: javax.XXX''' from the [[#EE_API_List|EE API list]]
 +
* Add directory %{_javadir}/javax.XXX that will contain symlinks to all implementation jar files and their dependencies
  
=== GCJ ===
+
At one time there '''CAN BE''' multiple API implementations but there '''MUST''' be at most one package having specific '''javax.XXX''' virtual provide.
Please refer to [[Packaging/GCJGuidelines]]  for GCJ-specific guidelines.
+
  
=== -devel packages ===
+
=== Packages using APIs ===
<code>-devel</code> packages don't really make sense for Java packages. Header files do not exist for Java packages.
+
Packages that need to use EE API '''SHOULD''' use:
 +
* '''Requires: javax.XXX''' from the [[#EE_API_List|EE API list]]
 +
* '''build-classpath javax.XXX''' or equivalent instead of relying on package-specific jar name.
  
== Specfile Template ==
 
=== ant ===
 
<pre>
 
Name:          # see normal package guidelines
 
Version:        # see normal package guidelines
 
Release:        1%{?dist}
 
Summary:        # see normal package guidelines (SNPG)
 
 
Group:          # SNPG
 
License:        # SNPG
 
URL:            # SNPG
 
Source0:        # SNPG
 
BuildRoot:      %{_tmppath}/%{name}-%{version}-%{release}-root-%(%{__id_u} -n)
 
 
BuildRequires:  jpackage-utils
 
 
BuildRequires:  java-devel
 
 
BuildRequires:  ant
 
 
Requires:      jpackage-utils
 
 
Requires:      java
 
 
%description
 
 
%package javadoc
 
Summary:        Javadocs for %{name}
 
Group:          Development Documentation
 
Requires:      %{name} = %{version}-%{release}
 
Requires:      jpackage-utils
 
 
%description javadoc
 
This package contains the API documentation for %{name}.
 
 
%package manual
 
Summary:        Manual for %{name}
 
Group:          Development Documentation
 
Requires:      jpackage-utils
 
Requires:      %{name} = %{version}-%{release}
 
 
%description manual
 
The manual for %{name}.
 
 
%prep
 
%setup -q
 
 
 
find -name '*.class' -exec rm -f '{}' \;
 
find -name '*.jar' -exec rm -f '{}' \;
 
 
 
 
%build
 
ant
 
 
%install
 
rm -rf $RPM_BUILD_ROOT
 
 
mkdir -p $RPM_BUILD_ROOT%{_javadir}
 
cp -p [build path to jar]  \
 
$RPM_BUILD_ROOT%{_javadir}/%{name}-%{version}.jar
 
 
 
mkdir -p $RPM_BUILD_ROOT%{_javadocdir}/%{name}
 
cp -rp [javadoc directory]  \
 
$RPM_BUILD_ROOT%{_javadocdir}/%{name}
 
 
%clean
 
rm -rf $RPM_BUILD_ROOT
 
 
%files
 
%defattr(-,root,root,-)
 
%{_javadir}/*
 
%doc
 
 
%files javadoc
 
%defattr(-,root,root,-)
 
%{_javadocdir}/%{name}
 
 
%files manual
 
%defattr(-,root,root,-)
 
%doc [manual directory] /*
 
 
%changelog
 
</pre>
 
 
=== maven ===
 
<pre>
 
Name:          # see normal package guidelines
 
Version:        # see normal package guidelines
 
Release:        1%{?dist}
 
Summary:        # see normal package guidelines (SNPG)
 
 
Group:          # SNPG
 
License:        # SNPG
 
URL:            # SNPG
 
Source0:        # SNPG
 
BuildRoot:      %{_tmppath}/%{name}-%{version}-%{release}-root-%(%{__id_u} -n)
 
 
BuildRequires:  jpackage-utils
 
 
BuildRequires:  java-devel
 
 
BuildRequires:  maven2
 
 
BuildRequires:    maven2-plugin-compiler
 
BuildRequires:    maven2-plugin-install
 
BuildRequires:    maven2-plugin-jar
 
BuildRequires:    maven2-plugin-javadoc
 
BuildRequires:    maven2-plugin-release
 
BuildRequires:    maven2-plugin-resources
 
BuildRequires:    maven2-plugin-surefire
 
 
Requires:      jpackage-utils
 
 
Requires(post):      jpackage-utils
 
Requires(postun):    jpackage-utils
 
 
Requires:      java
 
 
%description
 
 
%package javadoc
 
Summary:        Javadocs for %{name}
 
Group:          Development/Documentation
 
Requires:      %{name}-%{version}-%{release}
 
Requires:      jpackage-utils
 
 
%description javadoc
 
This package contains the API documentation for %{name}.
 
 
%package manual
 
Summary:        Manual for %{name}
 
Group:          Development/Documentation
 
Requires:      jpackage-utils
 
Requires:      %{name}-%{version}-%{release}
 
 
%description manual
 
The manual for %{name}.
 
 
%prep
 
%setup -q
 
 
%build
 
 
export MAVEN_REPO_LOCAL=$(pwd)/.m2/repository
 
mkdir -p $MAVEN_REPO_LOCAL
 
 
mvn-jpp \
 
-Dmaven.repo.local=$MAVEN_REPO_LOCAL \
 
install javadoc:javadoc
 
 
%install
 
rm -rf $RPM_BUILD_ROOT
 
 
mkdir -p $RPM_BUILD_ROOT%{_javadir}
 
cp -p [build path to jar]  \
 
$RPM_BUILD_ROOT%{_javadir}/%{name}-%{version}.jar
 
 
 
mkdir -p $RPM_BUILD_ROOT%{_javadocdir}/%{name}
 
cp -rp [javadoc directory]  \
 
$RPM_BUILD_ROOT%{_javadocdir}/%{name}
 
 
install -d -m 755 $RPM_BUILD_ROOT%{_datadir}/maven2/poms
 
install -pm 644 [path to pom]  \
 
$RPM_BUILD_ROOT%{_datadir}/maven2/poms/JPP-%{name}.pom
 
 
%add_to_maven_depmap org.apache.maven %{name} %{version} JPP %{name}
 
 
%clean
 
rm -rf $RPM_BUILD_ROOT
 
 
%post
 
%update_maven_depmap
 
 
%postun
 
%update_maven_depmap
 
 
%files
 
%defattr(-,root,root,-)
 
%{_datadir}/maven2/poms
 
%{_mavendepmapfragdir}
 
%{_javadir}/*
 
%doc
 
 
%files javadoc
 
%defattr(-,root,root,-)
 
%{_javadocdir}/%{name}
 
 
%files manual
 
%defattr(-,root,root,-)
 
%doc [manual directory] /*
 
 
%changelog
 
 
</pre>
 
 
For detailed instructions on the JPackage/Fedora maven, see the JPackage Maven rpm readme located [http://fedoraproject.org/wiki/Java/JPPMavenReadme here] .
 
  
 +
== Packaging JAR files that use JNI ==
 
{{Anchor|JNI}}
 
{{Anchor|JNI}}
== Packaging JAR files that use JNI ==
 
 
 
=== Applicability ===
 
=== Applicability ===
  
Java programs that wish to make calls into native libraries do so via the Java Native Interface (JNI).  A Java package uses JNI if it contains a .so
+
Java programs that wish to make calls into native libraries do so via the Java Native Interface (JNI).  A Java package uses JNI if it contains a .so file. Note that this file can be embedded within JAR files themselves.
  
{{Template:Warning}} Note that GCJ packages contain <code>.so</code>s in <code>%{_libdir}/gcj/%{name</code>} but they are not JNI .sos.
+
{{Template:Warning}} Note that GCJ packages contain <code>.so</code>s in <code>%{_libdir}/gcj/%{name}</code> but they are not JNI .sos.
  
 
=== Guideline ===
 
=== Guideline ===
  
JAR files that require JNI shared objects '''MUST''' be installed in <code>%{_libdir}/%{name</code>}.  The JNI shared objects themselves must also be installed in <code>%{_libdir}/%{name}</code>.  If the JNI-using code calls <code>System.loadLibrary</code> you'll have to patch it to use <code>System.load</code>, passing it the full path to the dynamic shared object.  If the package installs a wrapper script you'll need to manually add <code>%{_libdir}/%{name}/<jar filename></code> to <code>CLASSPATH</code>.  If you are depending on a JNI-using JAR file, you'll need to add it manually -- <code>build-classpath</code> will not find it.
+
* JNI packages '''MUST''' follow guidelines of ordinary Java packages with exceptions listed here
 
+
* JAR files using JNI or containing JNI shared objects themselves '''MUST''' be placed in <code>%{_jnidir}</code> and '''CAN BE''' symlinked to <code>%{_libdir}/%{name}</code>.
=== Rationale ===
+
* JNI shared objects '''MUST''' be placed in <code>%{_libdir}/%{name}</code>  
 
+
This is less convenient, but cleaner from a packaging point-of-view, than putting the JAR file in <code>%{_javadir</code>}, and putting the JNI shared object in  <code>%{_libdir</code>} to be loaded from the default library path.  First, JNI shared objects are <code>dlopen</code>'d, and <code>dlopen</code>'d shared objects should not be placed directly in <code>%{_libdir</code>} since they are application-private data, and not libraries meant to be linked to directly -- that is, not meant to be shared. Second, placing the JAR file in <code>%{_javadir</code>} causes the build-classpath script to always load it, even when running on a runtime environment of the wrong arch, meaning that the <code>System.loadLibrary</code> line would fail.
+
 
+
The plan is to eventually eliminate patching of the <code>System.loadLibrary</code> line and wrapper script by making <code>jpackage-utils</code> multilib aware.  This involves the following changes:  creating <code>%{_libdir}/java</code> and <code>%{_libdir}/jni</code> directories; giving JNI-containing packages the ability to require an architecture-specific runtime environment; adding support for specifying the required runtime architecture in a wrapper script; modifying <code>jpackage-utils</code>'s runtime scripts to search <code>%{_libdir}/java</code>; modifying IcedTea to look for JNI shared objects in <code>%{_libdir}/jni</code>.
+
 
+
The <code>%{_jnidir</code>} rpm macro defines the main JNI jar repository. Like <code>%{_javadir</code>} it is declined in <code>-ext</code> and <code>-x.y.z</code> variants. It follows exactly the same rules as the <code>%{_javadir</code>}-derived tree structure, except that it hosts JAR files that use JNI.
+
 
+
<code>%{_jnidir</code>} usually expands into <code>/usr/lib/java</code>.
+
  
== Things to avoid ==
+
{{admon/note|Note|If the JNI-using code calls <code>System.loadLibrary</code> you'll have to patch it to use <code>System.load</code>, passing it the full path to the dynamic shared object. You can look at the [[JavaSystemLoadExample|example]].}}
=== Pre-built JAR files / Other bundled software ===
+
Many Java projects re-ship their dependencies in their own releases.  This is unacceptable in Fedora.  All packages '''MUST''' be built from source and '''MUST''' enumerate their dependencies with <code>Requires</code>.  They '''MUST NOT''' build against or re-ship the pre-included JAR files but instead symlink out to the JAR files provided by dependencies.  There may arise rare cases that an upstream project is distributing JAR files that are actually not re-distributable
+
by Fedora.  In this situation, the JAR files themselves should not be redistributed -- even in the source zip.  A modified source zip should be created with some sort of modifier in the name (ex. -CLEAN) along with instructions for reproducing.  It is a good idea to have something similar to the following at the end of <code>%prep</code> (courtesy David Walluck):
+
  
<pre>
+
{{admon/note|Macro expansions|<code>%{_jnidir}</code> expands into <code>%{_prefix}/lib/java</code>, even on 64-bit systems. Java packages using JNI do not support multiarch installation.}}
JAR files=""
+
for j in $(find -name \*.jar); do
+
if [ ! -L $j ] ; then
+
JAR files="$JAR files $j"
+
fi
+
done
+
if [ ! -z "$JAR files" ] ; then
+
echo "These JAR files should be deleted and symlinked to system JAR files: $JAR files"
+
exit 1
+
fi
+
</pre>
+
  
=== Javadoc scriptlets ===
 
Older JPackage packages contained <code>%post</code> scriptlets creating <code>%ghost</code> symlinks.  These '''MUST''' not appear in Fedora Java packages and are actively being removed at JPackage.
 
  
=== Selected rpmlint issues ===
 
==== class-path-in-manifest ====
 
Use <code>sed</code> to remove <code>class-path</code> elements in <code>MANIFEST.MF</code> (or whatever file is being used as the JAR manifest) prior to JAR creation.  Example:
 
  
<pre>
 
sed -i '/class-path/I d' META-INF/MANIFEST.MF
 
</pre>
 
'''Will this preserve the line ending as the [http://java.sun.com/docs/books/tutorial/deployment/jar/downman.html this page]  says it must?'''
 
  
 +
[[Category:Java]]
 
[[Category:Packaging guidelines]]
 
[[Category:Packaging guidelines]]

Revision as of 16:15, 13 February 2014

These guidelines are laid out in order of relevance to packaging.


Contents

Introduction

This page represents Fedora guidelines for packaging libraries and applications written in Java and related languages using Java Virtual Machine as bytecode interpreter. It DOES NOT aim to extensively describe packaging techniques and tips. RPM macros and commands used here are documented in man pages. Furthermore a separate Java Packaging HOWTO describes Java packaging techniques in detail and includes examples, templates and documentation aimed at packagers and Java developers who are taking their first steps in Java RPM packaging.

Fedora Java packaging is originally based on JPackage Project standards. Over time we have diverged in packaging tools in most areas but we mostly keep backward compatibility with older packages that make use of JPackage standards.


Package naming

Packages MUST follow the standard Fedora package naming guidelines.

Java API documentation MUST be placed into a sub-package called %{name}-javadoc.

Release tags

Packages MUST follow the standard Fedora package versioning guidelines.

Pre-built dependencies

Packages MUST follow the standard Fedora dependency bundling guidelines.

In particular *.class and *.jar files from upstream releases MUST NOT be used during build of Fedora packages and they MUST NOT be included in binary RPM.

JAR file installation

The following applies to all JAR files except JNI-using JAR files and application-specific JAR files (ie. JAR files that can only reasonably be used as part of an application and therefore constitute application-private data).

Split JAR files

If a project offers the choice of packaging it as a single monolithic JAR or several ones, the split packaging SHOULD be preferred.

Installation directory

  • All architecture-independent JAR files MUST go into %{_javadir} or its subdirectory.

Filenames

  • If the package provides a single JAR file installed filename SHOULD be %{name}.jar.
  • If the package provides multiple JAR file, files SHOULD be installed in a %{name} subdirectory
  • Versioned JAR files (*-%{version}.jar) MUST NOT be installed unless the package is a compatibility package
  • Packages CAN provide alternative filenames as long as they do not conflict with other packages


Note.png
Note
Here %{name} refers either to package name, or name of subpackage where the jar is installed.

BuildRequires and Requires

Java packages MUST BuildRequire their respective build system:

  • BuildRequires: maven-local for packages built with Maven
  • BuildRequires: ant for packages built with ant
  • BuildRequires: java-devel for packages built with javac

Java binary packages or their dependencies MUST have Requires (generated by RPM or manual) on:

  • java-headless or java-headless >= 1:minimal_required_version
  • jpackage-utils

If java-headless requirement is insufficient package MUST have Requires:

  • java or java >= 1:minimal_required_version

Javadoc installation

  • Java API documentation uses a system known as Javadoc. All javadocs MUST be created and installed into a directory of %{_javadocdir}/%{name}.
  • Directory or symlink %{_javadocdir}/%{name}-%{version} SHOULD NOT exist.
  • The javadoc subpackage MUST be declared noarch even if main package is architecture specific.

No class-path in MANIFEST.MF

  • JAR files MUST NOT include classh-path entry inside META-INF/MANIFEST.MF

Hardcoded paths

Packages MUST NOT hardcode paths to JAR files they use. When package needs to reference a JAR file, packager SHOULD use one of tools designed to locating JAR files in the system.

Maven pom.xml files

If upstream project is shipping Maven pom.xml files, these MUST be installed. Additionally package MUST install mapping between upstream artifact and filesystem by using either %mvn_install or %add_maven_depmap macros.

Note.png
Additional documentation
Usage of %add_maven_depmap macro is documented in detail in Java Packaging HOWTO.


If upstream project does not ship Maven pom.xml file, official maven repository should be searched and if there are pom.xml files they SHOULD be installed.

If modifications to Maven pom.xml files are needed %pom_* family of macros SHOULD be used

Note.png
Additional documentation
Usage of %pom_* macros is documented in detail in Java Packaging HOWTO.

Wrapper Scripts

Applications wishing to provide a convenient method of execution SHOULD provide a wrapper script in %{_bindir}. Packages SHOULD use %jpackage_script to create these wrapper scripts.

Note.png
Additional documentation
Usage of %jpackage_script macro is documented in Java Packaging HOWTO.

Compatibility packages

In certain cases it might be necessary to create compatibility packages that provide older API/ABI level of the same library. However creating these compatibility packages is strongly discouraged. To standardize and simplify packaging of such compatibility packages following rules apply:

  • Compatibility packages MUST be named in the same way as original except addition of version to package name,
  • Any JAR and POM files MUST be versioned.
Note.png
Ant and Maven compatibility
build-classpath and related tools will resolve versioned jar files if versioned jar is asked for. Maven will use dependency information will return versioned jar if it matches the version asked for in the pom file.

Packaging and using EE APIs

There are a number of various project providing implementations for Java EE APIs. To simplify packaging and use of these APIs certain standardization is necessary.

EE API List

Following is a list of EE APIs as of Java EE 6[1] with chosen packages that provide implementations:

  • javax.activation - JDK
  • javax.annotation - JDK
  • javax.el - tomcat-el-2.2-api
  • javax.enterprise.inject - cdi-api
  • javax.inject - atinject
  • javax.jws - JDK
  • javax.mail - javamail
  • javax.management - JDK
  • javax.management.remote - JDK
  • javax.persistence - geronimo-jpa
  • javax.security.auth.message - geronimo-jaspic-spec
  • javax.servlet - tomcat-servlet-3.0-api
  • javax.servlet.jsp - glassfish-jsp/glassfish-jsp-api
  • javax.servlet.jsp.jstl - jakarta-taglibs-standard
  • javax.transaction - JDK
  • javax.ws.rs - jsr-311
  • javax.wsdl - wsdl4j
  • javax.xml - JDK
  • javax.xml.bind - JDK
  • javax.xml.rpc - axis
  • javax.xml.soap - JDK
  • javax.xml.stream - JDK
  • javax.xml.ws - JDK

Packages providing APIs

In addition to following generic guidelines they MUST:

  • Add Provides: javax.XXX from the EE API list
  • Add directory %{_javadir}/javax.XXX that will contain symlinks to all implementation jar files and their dependencies

At one time there CAN BE multiple API implementations but there MUST be at most one package having specific javax.XXX virtual provide.

Packages using APIs

Packages that need to use EE API SHOULD use:

  • Requires: javax.XXX from the EE API list
  • build-classpath javax.XXX or equivalent instead of relying on package-specific jar name.


Packaging JAR files that use JNI

Applicability

Java programs that wish to make calls into native libraries do so via the Java Native Interface (JNI). A Java package uses JNI if it contains a .so file. Note that this file can be embedded within JAR files themselves.

Stop (medium size).png Note that GCJ packages contain .sos in %{_libdir}/gcj/%{name} but they are not JNI .sos.

Guideline

  • JNI packages MUST follow guidelines of ordinary Java packages with exceptions listed here
  • JAR files using JNI or containing JNI shared objects themselves MUST be placed in %{_jnidir} and CAN BE symlinked to %{_libdir}/%{name}.
  • JNI shared objects MUST be placed in %{_libdir}/%{name}
Note.png
Note
If the JNI-using code calls System.loadLibrary you'll have to patch it to use System.load, passing it the full path to the dynamic shared object. You can look at the example.
Note.png
Macro expansions
%{_jnidir} expands into %{_prefix}/lib/java, even on 64-bit systems. Java packages using JNI do not support multiarch installation.