Modify jacoco runtime to reduce dependencies on core libs.

Previously, Offline's static initializer would eagerly create an
Agent, a process which has lots of dependencies. With this change,
Offline only eagerly creates an ExecutionDataStore, which is much more
lightweight. The Agent is only created when it's actually needed.

This makes it possible to instrument a lot of more core libraries
without creating a circular dependency at runtime (e.g. all of java.io
and java.nio, and most of java.util).

Bug: 64836607
Test: mvn clean install -Djdk.version=1.9 -Dbytecode.version=1.9 (in org.jacoco.build/)
Test: `cts-tradefed run cts-dev -m CtsLibcoreTestCases --test-arg com.android.compatibility.testtype.LibcoreTest:coverage:true` on a build with EMMA_INSTRUMENT=true and EMMA_INSTRUMENT_FRAMEWORK=true
Change-Id: Ib1bd1adcd1ea58935a588f442dc57f958841c6aa

1 files changed, 32 insertions, 6 deletions

diff --git a/org.jacoco.agent.rt/src/org/jacoco/agent/rt/internal/Offline.java b/org.jacoco.agent.rt/src/org/jacoco/agent/rt/internal/Offline.java
index 8b8b40c0..21a78bbd 100644
--- a/org.jacoco.agent.rt/src/org/jacoco/agent/rt/internal/Offline.java
+++ b/org.jacoco.agent.rt/src/org/jacoco/agent/rt/internal/Offline.java
@@ -13,6 +13,7 @@ package org.jacoco.agent.rt.internal;
 
 import java.util.Properties;
 
+import org.jacoco.core.data.ExecutionDataStore;
 import org.jacoco.core.runtime.AgentOptions;
 import org.jacoco.core.runtime.RuntimeData;
 
@@ -22,13 +23,19 @@ import org.jacoco.core.runtime.RuntimeData;
  */
 public final class Offline {
 
-	private static final RuntimeData DATA;
+	// BEGIN android-change
+	// private static final RuntimeData DATA;
+	private static final ExecutionDataStore DATA;
+	// END android-change
 	private static final String CONFIG_RESOURCE = "/jacoco-agent.properties";
 
 	static {
-		final Properties config = ConfigLoader.load(CONFIG_RESOURCE,
-				System.getProperties());
-		DATA = Agent.getInstance(new AgentOptions(config)).getData();
+		// BEGIN android-change
+		// final Properties config = ConfigLoader.load(CONFIG_RESOURCE,
+		//		System.getProperties());
+		// DATA = Agent.getInstance(new AgentOptions(config)).getData();
+		DATA = new ExecutionDataStore();
+		// END android-change
 	}
 
 	private Offline() {
@@ -48,8 +55,27 @@ public final class Offline {
 	 */
 	public static boolean[] getProbes(final long classid,
 			final String classname, final int probecount) {
-		return DATA.getExecutionData(Long.valueOf(classid), classname,
-				probecount).getProbes();
+		// BEGIN android-change
+		// return DATA.getExecutionData(Long.valueOf(classid), classname,
+		//		probecount).getProbes();
+		synchronized (DATA) {
+			return DATA.get(classid, classname, probecount).getProbes();
+		}
+		// END android-change
 	}
 
+	// BEGIN android-change
+	/**
+	 * Creates a default agent, using config loaded from the classpath resource and the system
+	 * properties, and a runtime data instance populated with the execution data accumulated by
+	 * the probes.
+	 *
+	 * @return the new agent
+	 */
+	static Agent createAgent() {
+		final Properties config = ConfigLoader.load(CONFIG_RESOURCE,
+				System.getProperties());
+		return Agent.getInstance(new AgentOptions(config), new RuntimeData(DATA));
+	}
+	// END android-change
 }