8187442: Xcheck:jni produces various "WARNING in native method" in launcher

Reviewed-by: ksrini, dholmes

src/java.base/share/native/libjli/java.c

@@ -1517,6 +1517,7 @@ NewPlatformString(JNIEnv *env, char *s)
             }
             str = (*env)->CallStaticObjectMethod(env, cls,
                     makePlatformStringMID, USE_STDERR, ary);
+            CHECK_EXCEPTION_RETURN_VALUE(0);
             (*env)->DeleteLocalRef(env, ary);
             return str;
         }
@@ -1585,13 +1586,16 @@ static jclass
 GetApplicationClass(JNIEnv *env)
 {
     jmethodID mid;
+    jclass appClass;
     jclass cls = GetLauncherHelperClass(env);
     NULL_CHECK0(cls);
     NULL_CHECK0(mid = (*env)->GetStaticMethodID(env, cls,
                 "getApplicationClass",
                 "()Ljava/lang/Class;"));
 
-    return (*env)->CallStaticObjectMethod(env, cls, mid);
+    appClass = (*env)->CallStaticObjectMethod(env, cls, mid);
+    CHECK_EXCEPTION_RETURN_VALUE(0);
+    return appClass;
 }
 
 static char* expandWildcardOnLongOpt(char* arg) {

test/jdk/tools/launcher/TestXcheckJNIWarnings.java

+/*
+ * 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.
+ */
+
+import java.io.File;
+import java.io.IOException;
+
+/**
+ * @test
+ * @bug 8187442
+ * @summary Launching app shouldn't produce any jni warnings.
+ * @modules jdk.compiler
+ *          jdk.zipfs
+ * @compile TestXcheckJNIWarnings.java
+ * @run main TestXcheckJNIWarnings
+ */
+public final class TestXcheckJNIWarnings extends TestHelper {
+
+    static void createJarFile(File testJar) throws IOException {
+        StringBuilder tsrc = new StringBuilder();
+        tsrc.append("public static void main(String... args) {\n");
+        tsrc.append("    System.out.println(\"Hello World\");\n");
+        tsrc.append("}\n");
+        createJar(testJar, new File("Foo"), tsrc.toString());
+    }
+
+    public static void main(String... args) throws IOException {
+        File testJarFile = new File("test.jar");
+        createJarFile(testJarFile);
+        TestResult tr = doExec(javaCmd, "-jar", "-Xcheck:jni",
+                               testJarFile.getName());
+        if (!tr.isOK()) {
+            System.out.println(tr);
+            throw new RuntimeException("test returned non-positive value");
+        }
+        if (!tr.contains("Hello World")) {
+            System.out.println(tr);
+            throw new RuntimeException("expected output not found");
+        }
+        if (tr.contains("WARNING")) {
+            System.out.println(tr);
+            throw new RuntimeException("WARNING was found in the output");
+        }
+    }
+}