commit a672cfbe2bcd1d768a6123a02f65f57ca6ec42f5
author Googler <noreply@google.com> Thu Apr 27 19:40:10 2017 +0200
committer Colin Cross <ccross@android.com> Thu Apr 27 18:57:52 2017 -0700
tree 51e65c7bdaf62af540f28121273e4492af328205
parent c5e345ca89228abdcff50024d8728a4e5bf87d44

Use system property for lambda dir if set

If system property that triggers writing lambda
classes is already set, use that value for the
lambda dump directory path. Otherwise, generate
a temporary dir path, and set it.

RELNOTES: n/a
PiperOrigin-RevId: 154440327
GitOrigin-RevId: a50a56cf9cd6c0f7c459b265213669b3a2f7ee5e
Change-Id: Ia273792f2f7e89758d962a3dfe051074691c0e59

java/com/google/devtools/build/android/desugar/Desugar.java

diff --git a/java/com/google/devtools/build/android/desugar/Desugar.java b/java/com/google/devtools/build/android/desugar/Desugar.java
index c4528ae..cd6b6ab 100644
--- a/java/com/google/devtools/build/android/desugar/Desugar.java
+++ b/java/com/google/devtools/build/android/desugar/Desugar.java
@@ -522,14 +522,20 @@
    * LambdaClassMaker generates lambda classes for us, but it does so by essentially simulating the
    * call to LambdaMetafactory that the JVM would make when encountering an invokedynamic.
    * LambdaMetafactory is in the JDK and its implementation has a property to write out ("dump")
-   * generated classes, which we take advantage of here. Set property before doing anything else
-   * since the property is read in the static initializer; if this breaks we can investigate setting
-   * the property when calling the tool.
+   * generated classes, which we take advantage of here. This property can be set externally, and in
+   * that case the specified directory is used as a temporary dir. Otherwise, it will be set here,
+   * before doing anything else since the property is read in the static initializer.
    */
   private static Path createAndRegisterLambdaDumpDirectory() throws IOException {
-    Path dumpDirectory = Files.createTempDirectory("lambdas");
-    System.setProperty(
-        LambdaClassMaker.LAMBDA_METAFACTORY_DUMPER_PROPERTY, dumpDirectory.toString());
+    String propertyValue = System.getProperty(LambdaClassMaker.LAMBDA_METAFACTORY_DUMPER_PROPERTY);
+    Path dumpDirectory;
+    if (propertyValue != null) {
+      dumpDirectory = Paths.get(propertyValue);
+    } else {
+      dumpDirectory = Files.createTempDirectory("lambdas");
+      System.setProperty(
+          LambdaClassMaker.LAMBDA_METAFACTORY_DUMPER_PROPERTY, dumpDirectory.toString());
+    }
 
     deleteTreeOnExit(dumpDirectory);
     return dumpDirectory;