ENT-1467: Make the deterministic JDK image compatible with IntelliJ. (#3416)

* Expand the deterministic JDK image to make it friendlier to IntelliJ.
* Fix Gradle always to use the latest deterministic rt.jar available.
* Write JDK items directly from Gradle.

build.gradle

@@ -83,7 +83,6 @@ buildscript {
     ext.jcabi_manifests_version = '1.1'
     ext.picocli_version = '3.0.0'
 
-    ext.deterministic_rt_version = '1.0-SNAPSHOT'
     // Name of the IntelliJ SDK created for the deterministic Java rt.jar.
     // ext.deterministic_idea_sdk = '1.8 (Deterministic)'
 

create-jdk8u/build.gradle

@@ -48,6 +48,7 @@ task makeJdk(type: Exec) {
 
 task runtimeJar(type: Jar, dependsOn: makeJdk) {
     baseName 'deterministic-rt'
+    inputs.dir "libs"
 
     from(zipTree("libs/rt.jar"))
     from(zipTree("libs/jce.jar"))

docs/source/deterministic-modules.rst

@@ -104,6 +104,24 @@ This is possible, but slightly tricky to configure because IntelliJ will not rec
 Gradle be configured to use the Project's SDK.
 
 Creating the Deterministic SDK
+    Gradle creates a suitable JDK image in the project's ``jdk8u-deterministic/jdk`` directory, and you can
+    configure IntelliJ to use this location for this SDK. However, you should also be aware that IntelliJ SDKs
+    are available for *all* projects to use.
+
+    To create this JDK image, execute the following:
+
+    .. code-block:: bash
+
+        $ gradlew jdk8u-deterministic:copyJdk
+
+    ..
+
+    Now select ``File/Project Structure/Platform Settings/SDKs`` and add a new JDK SDK with the
+    ``jdk8u-deterministic/jdk`` directory as its home. Rename this SDK to something like "1.8 (Deterministic)".
+
+    This *should* be sufficient for IntelliJ. However, if IntelliJ realises that this SDK does not contain a
+    full JDK then you will need to configure the new SDK by hand:
+
         #. Create a JDK Home directory with the following contents:
 
             ``jre/lib/rt.jar``
@@ -120,18 +138,6 @@ Creating the Deterministic SDK
 
            ..
 
-       .. note:: Gradle already creates this JDK in the project's ``jdk8u-deterministic/jdk`` directory, and you could
-                 configure IntelliJ to use this location as well. However, you should also be aware that IntelliJ SDKs
-                 are available for *all* projects to use.
-
-                 To create this deterministic JDK image, execute the following:
-
-                 .. code-block:: bash
-
-                     $ gradlew jdk8u-deterministic:copyJdk
-
-                 ..
-
         #. While IntelliJ is *not* running, locate the ``config/options/jdk.table.xml`` file in IntelliJ's configuration
            directory. Add an empty ``<jdk>`` section to this file:
 
@@ -148,10 +154,10 @@ Creating the Deterministic SDK
 
            ..
 
-    #. Open IntelliJ and select ``File/Project Structure/Platform Settings/SDKs``. The "1.8 (Deterministic)" SDK should
-       now be present. Select it and then click on the ``Classpath`` tab. Press the "Add" / "Plus" button to add
-       ``rt.jar`` to the SDK's classpath. Then select the ``Annotations`` tab and include the same JAR(s) as the other
-       SDKs.
+        #. Open IntelliJ and select ``File/Project Structure/Platform Settings/SDKs``. The "1.8 (Deterministic)" SDK
+           should now be present. Select it and then click on the ``Classpath`` tab. Press the "Add" / "Plus" button to
+           add ``rt.jar`` to the SDK's classpath. Then select the ``Annotations`` tab and include the same JAR(s) as
+           the other SDKs.
 
 Configuring the Corda Project
     #. Open the root ``build.gradle`` file and define this property:

jdk8u-deterministic/build.gradle

@@ -8,23 +8,39 @@ repositories {
 }
 
 ext {
-    jdk_home = "$projectDir/jdk"
+    jdk_home = "$projectDir/jdk".toString()
     rt_jar = "$jdk_home/jre/lib/rt.jar".toString()
 }
 
 configurations {
-    jdk
+    jdk.resolutionStrategy {
+        cacheChangingModulesFor 0, 'seconds'
+    }
 }
 
 dependencies {
-    jdk "net.corda:deterministic-rt:$deterministic_rt_version:api"
+    // Ensure everyone uses the latest SNAPSHOT.
+    jdk "net.corda:deterministic-rt:latest.integration:api"
 }
 
 task copyJdk(type: Copy) {
+    outputs.dir jdk_home
+
     from(configurations.jdk.asPath) {
         rename 'deterministic-rt-(.*).jar', 'rt.jar'
     }
     into "$jdk_home/jre/lib"
+
+    doLast {
+        def eol = System.getProperty('line.separator')
+        file("$jdk_home/release").write "JAVA_VERSION=\"1.8.0_172\"$eol"
+        mkdir "$jdk_home/bin"
+        file("$jdk_home/bin/javac").with {
+            write "#!/bin/sh\necho \"javac 1.8.0_172\"\n"
+            setExecutable true, false
+            return
+        }
+    }
 }
 
 assemble.dependsOn copyJdk