Follow latest version automatically (spotbugs#195)

* upgrade Gradle to use WriteProperties task

* use resource to follow the latest release automatically

* fix test for classes built by Java7

build.gradle

@@ -17,6 +17,6 @@ subprojects {
 }
 
 wrapper {
-  gradleVersion = '3.2.1'
+  gradleVersion = '3.5'
   distributionType = Wrapper.DistributionType.ALL
 }

gradle/wrapper/gradle-wrapper.properties

@@ -3,4 +3,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-3.2.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-3.5-all.zip

gradlePlugin/.gitignore

@@ -0,0 +1 @@
+src/main/resources/spotbugs-gradle-plugin.properties

gradlePlugin/build.gradle

@@ -38,3 +38,10 @@ pluginBundle {
     }
   }
 }
+
+task processVersionFile(type: WriteProperties) {
+  outputFile file('src/main/resources/spotbugs-gradle-plugin.properties')
+
+  property 'spotbugs-version', project(':spotbugs').version
+}
+tasks.processResources.dependsOn processVersionFile

gradlePlugin/src/main/java/com/github/spotbugs/SpotBugsPlugin.java

@@ -1,7 +1,12 @@
 package com.github.spotbugs;
 
 import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.UncheckedIOException;
+import java.net.URL;
 import java.util.Collection;
+import java.util.Properties;
 import java.util.concurrent.Callable;
 
 import org.gradle.api.Action;
@@ -15,6 +20,8 @@
 import org.gradle.api.resources.TextResource;
 import org.gradle.api.tasks.SourceSet;
 
+import com.google.common.annotations.VisibleForTesting;
+import com.google.common.io.Resources;
 import com.google.common.util.concurrent.Callables;
 
 /**
@@ -33,7 +40,6 @@
  */
 public class SpotBugsPlugin extends AbstractCodeQualityPlugin<SpotBugsTask> {
 
-    public static final String DEFAULT_FINDBUGS_VERSION = "3.1.0-RC2";
     private FindBugsExtension extension;
 
     @Override
@@ -61,10 +67,22 @@ private void configureFindBugsConfigurations() {
     @Override
     protected CodeQualityExtension createExtension() {
         extension = project.getExtensions().create("spotbugs", FindBugsExtension.class, project);
-        extension.setToolVersion(DEFAULT_FINDBUGS_VERSION);
+        extension.setToolVersion(loadToolVersion());
         return extension;
     }
 
+    @VisibleForTesting
+    String loadToolVersion() {
+        URL url = Resources.getResource("spotbugs-gradle-plugin.properties");
+        try (InputStream input = url.openStream()) {
+            Properties prop = new Properties();
+            prop.load(input);
+            return prop.getProperty("spotbugs-version");
+        } catch (IOException e) {
+            throw new UncheckedIOException(e);
+        }
+    }
+
     @Override
     protected void configureTaskDefaults(SpotBugsTask task, String baseName) {
         task.setPluginClasspath(project.getConfigurations().getAt("findbugsPlugins"));

gradlePlugin/src/test/java/com/github/spotbugs/SpotBugsPluginTest.java

@@ -1,5 +1,8 @@
 package com.github.spotbugs;
 
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.CoreMatchers.notNullValue;
+
 import java.io.File;
 import java.util.Arrays;
 
@@ -40,4 +43,10 @@ public void TestFindBugsTasksExist() throws Exception{
     assertTrue(result.getOutput().contains("findbugsMain"));
     assertTrue(result.getOutput().contains("findbugsTest"));
   }
+
+  @Test
+  public void testLoadToolVersion() {
+    SpotBugsPlugin plugin = new SpotBugsPlugin();
+    assertThat(plugin.loadToolVersion(), is(notNullValue()));
+  }
 }

spotbugs-tests/src/test/java/edu/umd/cs/findbugs/detect/FindUnsatisfiedObligationTest.java

@@ -22,7 +22,7 @@ public class FindUnsatisfiedObligationTest {
      */
     @Test
     public void testIssue60() {
-        BugCollection bugCollection = spotbugs.performAnalysis(Paths.get("../spotbugsTestCases/build/classes/main/Issue60.class"));
+        BugCollection bugCollection = spotbugs.performAnalysis(Paths.get("../spotbugsTestCases/build/classes/main/lambdas/Issue60.class"));
         assertThat(bugCollection, is(emptyIterable()));
     }
 }

spotbugsTestCases/build.gradle

@@ -32,9 +32,12 @@ tasks.withType(JavaCompile).all {
 
 task classesJava7(type:JavaCompile) {
   exclude '**/*jdk8.java'
+  exclude '**/lambdas/**'
   sourceCompatibility = '1.7'
   targetCompatibility = '1.7'
   destinationDir = file("$buildDir/classes-jdk7")
+  classpath = sourceSets.main.compileClasspath
+  source = sourceSets.main.java
 }
 
 tasks['build'].dependsOn classesJava7

spotbugsTestCases/src/java/Issue60.java → spotbugsTestCases/src/java/lambdas/Issue60.java

@@ -1,3 +1,5 @@
+package lambdas;
+
 import java.io.IOException;
 import java.io.InputStream;
 import java.net.URL;