8174694: improve error message shown when main class can't be loaded
authorvromero
Wed, 15 Feb 2017 17:00:22 -0800
changeset 43809 c3669a70a7ab
parent 43808 c0a93657773d
child 43810 a8fca792a14b
8174694: improve error message shown when main class can't be loaded Reviewed-by: ksrini, alanb
jdk/src/java.base/share/classes/sun/launcher/LauncherHelper.java
jdk/src/java.base/share/classes/sun/launcher/resources/launcher.properties
jdk/test/tools/launcher/MainClassCantBeLoadedTest.java
--- a/jdk/src/java.base/share/classes/sun/launcher/LauncherHelper.java	Wed Feb 15 16:18:22 2017 -0800
+++ b/jdk/src/java.base/share/classes/sun/launcher/LauncherHelper.java	Wed Feb 15 17:00:22 2017 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2007, 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2007, 2017, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -638,10 +638,12 @@
                         String ncn = Normalizer.normalize(cn, Normalizer.Form.NFC);
                         mainClass = Class.forName(ncn, false, scl);
                     } catch (NoClassDefFoundError | ClassNotFoundException cnfe1) {
-                        abort(cnfe1, "java.launcher.cls.error1", cn);
+                        abort(cnfe1, "java.launcher.cls.error1", cn,
+                                cnfe1.getClass().getCanonicalName(), cnfe1.getMessage());
                     }
                 } else {
-                    abort(cnfe, "java.launcher.cls.error1", cn);
+                    abort(cnfe, "java.launcher.cls.error1", cn,
+                            cnfe.getClass().getCanonicalName(), cnfe.getMessage());
                 }
             }
         } catch (LinkageError le) {
--- a/jdk/src/java.base/share/classes/sun/launcher/resources/launcher.properties	Wed Feb 15 16:18:22 2017 -0800
+++ b/jdk/src/java.base/share/classes/sun/launcher/resources/launcher.properties	Wed Feb 15 17:00:22 2017 -0800
@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2007, 2016, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2007, 2017, Oracle and/or its affiliates. All rights reserved.
 # DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 #
 # This code is free software; you can redistribute it and/or modify it
@@ -175,7 +175,8 @@
 \                      override default icon displayed in dock\n\n
 
 java.launcher.cls.error1=\
-    Error: Could not find or load main class {0}
+    Error: Could not find or load main class {0}\n\
+    Caused by: {1}: {2}
 java.launcher.cls.error2=\
     Error: Main method is not {0} in class {1}, please define the main method as:\n\
 \   public static void main(String[] args)
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/tools/launcher/MainClassCantBeLoadedTest.java	Wed Feb 15 17:00:22 2017 -0800
@@ -0,0 +1,98 @@
+/*
+ * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * @test
+ * @bug 8174694
+ * @summary improve error message shown when main class can't be loaded
+ * @compile MainClassCantBeLoadedTest.java
+ * @run main MainClassCantBeLoadedTest
+ */
+
+import java.io.*;
+import java.util.*;
+
+public class MainClassCantBeLoadedTest extends TestHelper {
+    private MainClassCantBeLoadedTest(){}
+
+    @Test
+    void testLoadingClassWithMissingSuper() throws Exception {
+        if (!isEnglishLocale()) {
+            return;
+        }
+
+        File cwd = new File(".");
+        File srcDir = new File(cwd, "src");
+        if (srcDir.exists()) {
+            recursiveDelete(srcDir);
+        }
+        srcDir.mkdirs();
+
+        /* we want to generate two classes A and B, where B is the superclass of A
+         * class A has a main method
+         */
+        ArrayList<String> scratchpad = new ArrayList<>();
+        scratchpad.add("public class A extends B {");
+        scratchpad.add("    public static void main(String... args) {}");
+        scratchpad.add("}");
+        createFile(new File(srcDir, "A.java"), scratchpad);
+
+        scratchpad.clear();
+        scratchpad.add("class B {}");
+        createFile(new File(srcDir, "B.java"), scratchpad);
+
+        // let's compile both
+        TestResult trCompilation = doExec(javacCmd,
+                "-d", "out",
+                new File(srcDir, "A.java").toString(),
+                new File(srcDir, "B.java").toString());
+        if (!trCompilation.isOK()) {
+            System.err.println(trCompilation);
+            throw new RuntimeException("Error: compiling");
+        }
+
+        // and now B is removed
+        File outDir = new File(cwd, "out");
+        File bClass = new File(outDir, "B.class");
+        bClass.delete();
+
+        // if A is executed
+        TestResult trExecution = doExec(javaCmd, "-cp", "out", "A");
+        // then this error message should be generated
+        trExecution.contains("Error: Could not find or load main class A");
+        trExecution.contains("Caused by: java.lang.NoClassDefFoundError: B");
+        if (!trExecution.testStatus)
+            System.err.println(trExecution);
+    }
+
+    public static void main(String[] args) throws Exception {
+        MainClassCantBeLoadedTest a = new MainClassCantBeLoadedTest();
+        a.run(args);
+        if (testExitValue > 0) {
+            System.out.println("Total of " + testExitValue + " failed");
+            throw new RuntimeException("Test failed");
+        } else {
+            System.out.println("Test passed");
+        }
+    }
+}