8295884: Implement IDE support for Eclipse

Reviewed-by: erikj

.gitignore

@@ -18,3 +18,6 @@ NashornProfile.txt
 /src/utils/LogCompilation/target/
 /.project/
 /.settings/
+/.project
+/.classpath
+/.cproject

doc/ide.html

@@ -79,6 +79,45 @@ <h4 id="visual-studio">Visual Studio</h4>
 <code>ide\hotspot-visualstudio</code> subfolder of the build output
 folder. The file can be opened in Visual Studio via
 <code>File -&gt; Open -&gt; Project/Solution</code>.</p>
+<h4 id="eclipse-cdt">Eclipse CDT</h4>
+<p>The make system can generate an Eclipse CDT Workspace that enables
+Eclipse indexing for the C and C++ sources throughout the entire
+codebase, as well as registering all common make targets to be runnable
+from the Eclipse explorer. This can be done after configuring by
+running:</p>
+<pre><code>make eclipse-native-env</code></pre>
+<p>After this is run, simply open and import the workspace in Eclipse
+through
+<code>File -&gt; Import -&gt; Projects from Folder or Archive</code> and
+at <code>Import source</code> click on the directory
+<code>ide\eclipse</code>, which can be found in the build output
+folder.</p>
+<p>If this doesn't work, you can also try
+<code>File -&gt; Import -&gt; Existing Projects into Workspace</code>
+instead.</p>
+<p>Setting up an Eclipse Workspace is relatively lightweight compared to
+other supported IDEs, but requires that your CDT installation has Cross
+GCC support enabled at the moment, even if you aren't cross compiling.
+The Visual C++ compiler is, at present, not supported as an indexer.</p>
+<p>If desired, you can instead request make to only include indexing
+support for just the Java Virtual Machine instead of the entire native
+codebase, by running:</p>
+<pre><code>make eclipse-hotspot-env</code></pre>
+<p>If you think your particular Eclipse installation can handle the
+strain, the make system also supports generating a combined Java and
+C/C++ Workspace for Eclipse which can then conveniently switch between
+Java and C/C++ natures during development by running:</p>
+<pre><code>make eclipse-mixed-env</code></pre>
+<p>Do note that this generates all features that come with both Java and
+C/C++ natures.</p>
+<p>By default, the Eclipse Workspace is located in the ide subdirectory
+in the build output. To share the JDK's source directory with the
+Eclipse Workspace, you can instead run:</p>
+<pre><code>make eclipse-shared-&lt;ENV&gt;-env</code></pre>
+<p>Eclipse support in the JDK is relatively new, so do keep in mind that
+not everything may work at the moment. As such, the resulting Workspace
+also has compilation database parsing support enabled, so you can pass
+Eclipse the compile commands file (see below) if all else fails.</p>
 <h4 id="compilation-database">Compilation Database</h4>
 <p>The make system can generate generic native code indexing support in
 the form of a <a
@@ -105,5 +144,28 @@ <h4 id="intellij-idea">IntelliJ IDEA</h4>
 <p>In order to run the tests from the IDE, you can use the JTReg plugin.
 Instructions for building and using the plugin can be found <a
 href="https://github.com/openjdk/jtreg/tree/master/plugins/idea">here</a>.</p>
+<h4 id="eclipse">Eclipse</h4>
+<p>Eclipse JDT is a widely used Java IDE and has been for a very long
+time, being a popular choice alongside IntelliJ IDEA for Java
+development. Likewise, the JDK now includes support for developing its
+Java sources with Eclipse, which can be achieved by setting up a Java
+Workspace by running:</p>
+<pre><code>make eclipse-java-env</code></pre>
+<p>After the workspace has been generated you can import it in the same
+way as you would with Eclipse CDT:</p>
+<p>Follow
+<code>File -&gt; Import -&gt; Projects from Folder or Archive</code> and
+select the <code>ide\eclipse</code> directory in the build output folder
+to import the newly created Java Workspace.</p>
+<p>If doing so results in an error, you can also import the JDK via
+<code>File -&gt; Import -&gt; Existing Projects into Workspace</code> as
+a last resort.</p>
+<p>Alternatively, if you want a Java Workspace inside the JDK's source
+directory, you can instead run:</p>
+<pre><code>make eclipse-shared-java-env</code></pre>
+<p>As mentioned above for Eclipse CDT, you can create a combined Java
+and C/C++ Workspace which can conveniently switch between Java and C/C++
+natures during development by running:</p>
+<pre><code>make eclipse-mixed-env</code></pre>
 </body>
 </html>

doc/ide.md

@@ -56,6 +56,63 @@ This creates a file named `jvm.vcxproj` in `ide\hotspot-visualstudio`
 subfolder of the build output folder. The file can be opened in Visual Studio
 via `File -> Open -> Project/Solution`.
 
+#### Eclipse CDT
+
+The make system can generate an Eclipse CDT Workspace that enables Eclipse
+indexing for the C and C++ sources throughout the entire codebase, as well as
+registering all common make targets to be runnable from the Eclipse explorer.
+This can be done after configuring by running:
+
+```
+make eclipse-native-env
+```
+
+After this is run, simply open and import the workspace in Eclipse through
+`File -> Import -> Projects from Folder or Archive` and at
+`Import source` click on the directory `ide\eclipse`, which can be
+found in the build output folder.
+
+If this doesn't work, you can also try
+`File -> Import -> Existing Projects into Workspace`
+instead.
+
+Setting up an Eclipse Workspace is relatively lightweight compared to other
+supported IDEs, but requires that your CDT installation has Cross GCC support
+enabled at the moment, even if you aren't cross compiling. The Visual C++
+compiler is, at present, not supported as an indexer.
+
+If desired, you can instead request make to only include indexing support for
+just the Java Virtual Machine instead of the entire native codebase, by running:
+
+```
+make eclipse-hotspot-env
+```
+
+If you think your particular Eclipse installation can handle the strain, the
+make system also supports generating a combined Java and C/C++ Workspace for
+Eclipse which can then conveniently switch between Java and C/C++ natures
+during development by running:
+
+```
+make eclipse-mixed-env
+```
+
+Do note that this generates all features that come with both Java and C/C++
+natures.
+
+By default, the Eclipse Workspace is located in the ide subdirectory in the
+build output. To share the JDK's source directory with the Eclipse Workspace,
+you can instead run:
+
+```
+make eclipse-shared-<ENV>-env
+```
+
+Eclipse support in the JDK is relatively new, so do keep in mind that not
+everything may work at the moment. As such, the resulting Workspace also
+has compilation database parsing support enabled, so you can pass Eclipse
+the compile commands file (see below) if all else fails.
+
 #### Compilation Database
 
 The make system can generate generic native code indexing support in the form of
@@ -96,3 +153,40 @@ as the SDK to use.
 In order to run the tests from the IDE, you can use the JTReg plugin.
 Instructions for building and using the plugin can be found
 [here](https://github.com/openjdk/jtreg/tree/master/plugins/idea).
+
+#### Eclipse
+
+Eclipse JDT is a widely used Java IDE and has been for a very long time, being
+a popular choice alongside IntelliJ IDEA for Java development. Likewise, the
+JDK now includes support for developing its Java sources with Eclipse, which
+can be achieved by setting up a Java Workspace by running:
+
+```
+make eclipse-java-env
+```
+
+After the workspace has been generated you can import it in the same way as
+you would with Eclipse CDT:
+
+Follow `File -> Import -> Projects from Folder or Archive` and select the
+`ide\eclipse` directory in the build output folder to import the newly created
+Java Workspace.
+
+If doing so results in an error, you can also import the JDK via
+`File -> Import -> Existing Projects into Workspace`
+as a last resort.
+
+Alternatively, if you want a Java Workspace inside the JDK's source directory,
+you can instead run:
+
+```
+make eclipse-shared-java-env
+```
+
+As mentioned above for Eclipse CDT, you can create a combined Java and C/C++
+Workspace which can conveniently switch between Java and C/C++ natures during
+development by running:
+
+```
+make eclipse-mixed-env
+```

make/Main.gmk

@@ -257,6 +257,46 @@ $(eval $(call SetupTarget, hotspot-ide-project, \
     ARGS := -I$(TOPDIR)/make/hotspot, \
 ))
 
+$(eval $(call SetupTarget, eclipse-java-env, \
+    MAKEFILE := ide/eclipse/CreateWorkspace, \
+    ARGS := --always-make WORKSPACE=java SHARED=false, \
+))
+
+$(eval $(call SetupTarget, eclipse-hotspot-env, \
+    MAKEFILE := ide/eclipse/CreateWorkspace, \
+    ARGS := --always-make WORKSPACE=hotspot SHARED=false, \
+))
+
+$(eval $(call SetupTarget, eclipse-native-env, \
+    MAKEFILE := ide/eclipse/CreateWorkspace, \
+    ARGS := --always-make WORKSPACE=native SHARED=false, \
+))
+
+$(eval $(call SetupTarget, eclipse-mixed-env, \
+    MAKEFILE := ide/eclipse/CreateWorkspace, \
+    ARGS := --always-make SHARED=false, \
+))
+
+$(eval $(call SetupTarget, eclipse-shared-java-env, \
+    MAKEFILE := ide/eclipse/CreateWorkspace, \
+    ARGS := --always-make WORKSPACE=java SHARED=true, \
+))
+
+$(eval $(call SetupTarget, eclipse-shared-hotspot-env, \
+    MAKEFILE := ide/eclipse/CreateWorkspace, \
+    ARGS := --always-make WORKSPACE=hotspot SHARED=true, \
+))
+
+$(eval $(call SetupTarget, eclipse-shared-native-env, \
+    MAKEFILE := ide/eclipse/CreateWorkspace, \
+    ARGS := --always-make WORKSPACE=native SHARED=true, \
+))
+
+$(eval $(call SetupTarget, eclipse-shared-mixed-env, \
+    MAKEFILE := ide/eclipse/CreateWorkspace, \
+    ARGS := --always-make SHARED=true, \
+))
+
 ALL_TARGETS += $(HOTSPOT_VARIANT_TARGETS) $(HOTSPOT_VARIANT_GENSRC_TARGETS) \
     $(HOTSPOT_VARIANT_LIBS_TARGETS)