Switch to methodHandles (#119)

mojohaus · Feb 9, 2019 · 8c8162d · 8c8162d
1 parent cdd4061
commit 8c8162d
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Showing 7 changed files with 24 additions and 50 deletions.
diff --git a/pom.xml b/pom.xml
@@ -228,6 +228,9 @@
             <artifactId>java17</artifactId>
             <version>1.0</version>
           </signature>
+          <ignores>
+            <ignore>java.lang.invoke.MethodHandle</ignore>
+          </ignores>
         </configuration>
       </plugin>
       <plugin>

diff --git a/src/it/mrm/repository/parent-0.1.pom b/src/it/mrm/repository/parent-0.1.pom
@@ -58,7 +58,7 @@
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-compiler-plugin</artifactId>
-          <version>3.1</version>
+          <version>3.8.0</version>
         </plugin>
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>

diff --git a/src/it/projects/jigsaw/pom.xml b/src/it/projects/jigsaw/pom.xml
@@ -17,10 +17,8 @@
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-compiler-plugin</artifactId>
-        <version>3.6.1</version>
         <configuration>
-          <source>9</source>
-          <target>9</target>
+          <release>9</release>
         </configuration>
       </plugin>
       <plugin>

diff --git a/src/it/projects/mexec-29-non-static/verify.groovy b/src/it/projects/mexec-29-non-static/verify.groovy
@@ -17,18 +17,5 @@
  * under the License.
  */
 
-import java.io.*
-import java.util.*
-
-t = new IntegrationBase()
-
-def buildLog = new File( basedir, "build.log" )
-
-t.checkExistenceAndContentOfAFile(buildLog, [
-  "[DEBUG] Setting accessibility to true in order to invoke main().",
-  "org.apache.maven.plugin.MojoExecutionException: Can't call main(String[])-method because it is not static.",
-])
-
-
-
-
+def buildLog = new File( basedir, 'build.log' )
+assert buildLog.text.contains('The specified mainClass doesn\'t contain a main method with appropriate signature.')
diff --git a/src/it/projects/mexec-29-wrong-signature/verify.groovy b/src/it/projects/mexec-29-wrong-signature/verify.groovy
@@ -17,15 +17,5 @@
  * under the License.
  */
 
- import java.io.*
- import java.util.*
-
- t = new IntegrationBase()
-
- def buildLog = new File( basedir, "build.log" )
-
- t.checkExistenceAndContentOfAFile(buildLog, [
-   "java.lang.Exception: The specified mainClass doesn't contain a main method with appropriate signature."
- ])
-
-
+def buildLog = new File( basedir, 'build.log' )
+assert buildLog.text.contains('java.lang.NoSuchMethodException: no such method: org.codehaus.mojo.exec.Main.main(String[])void')
diff --git a/src/it/projects/mexec-98/verify.groovy b/src/it/projects/mexec-98/verify.groovy
@@ -18,4 +18,4 @@
  */
 File log = new File(basedir, 'build.log')
 assert log.exists()
-assert log.getText().contains( "Can't call main(String[])-method because it is not static.")
+assert log.getText().contains( "The specified mainClass doesn't contain a main method with appropriate signature.")
diff --git a/src/main/java/org/codehaus/mojo/exec/ExecJavaMojo.java b/src/main/java/org/codehaus/mojo/exec/ExecJavaMojo.java
@@ -20,9 +20,10 @@
  */
 
 import java.io.File;
+import java.lang.invoke.MethodHandle;
+import java.lang.invoke.MethodHandles;
+import java.lang.invoke.MethodType;
 import java.lang.reflect.InvocationTargetException;
-import java.lang.reflect.Method;
-import java.lang.reflect.Modifier;
 import java.net.MalformedURLException;
 import java.net.URL;
 import java.net.URLClassLoader;
@@ -266,22 +267,17 @@ public void run()
             {
                 try
                 {
-                    Method main =
-                        Thread.currentThread().getContextClassLoader().loadClass( mainClass ).getMethod( "main",
-                                                                                                         new Class[] {
-                                                                                                             String[].class } );
-                    if ( !main.isAccessible() )
-                    {
-                        getLog().debug( "Setting accessibility to true in order to invoke main()." );
-                        main.setAccessible( true );
-                    }
-                    if ( !Modifier.isStatic( main.getModifiers() ) )
-                    {
-                        throw new MojoExecutionException( "Can't call main(String[])-method because it is not static." );
-                    }
-                    main.invoke( null, new Object[] { arguments } );
+                    Class<?> bootClass = Thread.currentThread().getContextClassLoader().loadClass( mainClass );
+
+                    MethodHandles.Lookup publicLookup = MethodHandles.publicLookup();
+
+                    MethodHandle mainHandle =
+                        publicLookup.findStatic( bootClass, "main",
+                                                 MethodType.methodType( void.class, String[].class ) );
+
+                    mainHandle.invoke( arguments );
                 }
-                catch ( NoSuchMethodException e )
+                catch ( IllegalAccessException e )
                 { // just pass it on
                     Thread.currentThread().getThreadGroup().uncaughtException( Thread.currentThread(),
                                                                                new Exception( "The specified mainClass doesn't contain a main method with appropriate signature.",
@@ -292,7 +288,7 @@ public void run()
                    Throwable exceptionToReport = e.getCause() != null ? e.getCause() : e;
                    Thread.currentThread().getThreadGroup().uncaughtException( Thread.currentThread(), exceptionToReport );
                 }
-                catch ( Exception e )
+                catch ( Throwable e )
                 { // just pass it on
                     Thread.currentThread().getThreadGroup().uncaughtException( Thread.currentThread(), e );
                 }