Merge pull request #616 from graalvm/fix-jdk-graalvm-error-message

Fix error message when the JDK is not a GraalVM

Author: eregon

native-gradle-plugin/src/main/java/org/graalvm/buildtools/gradle/internal/NativeImageExecutableLocator.java

@@ -91,29 +91,29 @@ public static File findNativeImageExecutable(Property<JavaLauncher> javaLauncher
             executablePath = metadata.getInstallationPath().file("bin/" + NATIVE_IMAGE_EXE).getAsFile();
         }
 
-        try {
-            if (!executablePath.exists()) {
-                logger.log("Native Image executable wasn't found. We will now try to download it. ");
-                File graalVmHomeGuess = executablePath.getParentFile();
-
-                File guPath = graalVmHomeGuess.toPath().resolve(GU_EXE).toFile();
-                if (!guPath.exists()) {
-                    throw new GradleException("'" + GU_EXE + "' at '" + guPath + "' tool wasn't found. This probably means that JDK at isn't a GraalVM distribution.");
-                }
-                ExecResult res = execOperations.exec(spec -> {
-                    spec.args("install", "native-image");
-                    spec.setExecutable(Paths.get(graalVmHomeGuess.getAbsolutePath(), GU_EXE));
-                });
-                if (res.getExitValue() != 0) {
-                    throw new GradleException("Native Image executable wasn't found, and '" + GU_EXE + "' tool failed to install it.");
-                }
-                diagnostics.withGuInstall();
+        File graalVmHomeGuess = executablePath.getParentFile();
+        File guPath = graalVmHomeGuess.toPath().resolve(GU_EXE).toFile();
+        if (guPath.exists() && !executablePath.exists()) {
+            logger.log("Native Image executable wasn't found. We will now try to download it. ");
+
+            ExecResult res = execOperations.exec(spec -> {
+                spec.args("install", "native-image");
+                spec.setExecutable(Paths.get(graalVmHomeGuess.getAbsolutePath(), GU_EXE));
+            });
+            if (res.getExitValue() != 0) {
+                throw new GradleException("Native Image executable wasn't found, and '" + GU_EXE + "' tool failed to install it.\n" +
+                        "Make sure to declare the GRAALVM_HOME or JAVA_HOME environment variable or install GraalVM with " +
+                        "native-image in a standard location recognized by Gradle Java toolchain support");
             }
-        } catch (GradleException e) {
-            throw new GradleException("Determining GraalVM installation failed with message: " + e.getMessage() + "\n\n"
-                                      + "Make sure to declare the GRAALVM_HOME environment variable or install GraalVM with " +
-                                      "native-image in a standard location recognized by Gradle Java toolchain support");
+            diagnostics.withGuInstall();
         }
+
+        if (!executablePath.exists()) {
+            throw new GradleException(executablePath + " wasn't found. This probably means that JDK isn't a GraalVM distribution.\n" +
+                    "Make sure to declare the GRAALVM_HOME or JAVA_HOME environment variable or install GraalVM with" +
+                    "native-image in a standard location recognized by Gradle Java toolchain support");
+        }
+
         diagnostics.withExecutablePath(executablePath);
         return executablePath;
     }

native-maven-plugin/src/main/java/org/graalvm/buildtools/utils/NativeImageConfigurationUtils.java

@@ -69,34 +69,31 @@ public static Path getJavaHomeNativeImage(String javaHomeVariable, Boolean failF
 
         Path graalHomePath = Paths.get(graalHome);
         Path nativeImageExe = graalHomePath.resolve("bin").resolve(NATIVE_IMAGE_EXE);
+        Path guExe = graalHomePath.resolve("bin").resolve(GU_EXE);
 
-        if (!Files.exists(nativeImageExe)) {
-            Path guExe = graalHomePath.resolve("bin").resolve(GU_EXE);
-            if (Files.exists(guExe)) {
-                ProcessBuilder processBuilder = new ProcessBuilder(guExe.toString(), "install", "native-image");
-                processBuilder.inheritIO();
-                try {
-                    Process nativeImageFetchingProcess = processBuilder.start();
-                    if (nativeImageFetchingProcess.waitFor() != 0) {
-                        throw new MojoExecutionException("native-image was not found, and '" + GU_EXE + "' tool failed to install it.");
-                    }
-                } catch (MojoExecutionException | IOException | InterruptedException e) {
-                    throw new MojoExecutionException("Determining GraalVM installation failed with message: " + e.getMessage());
+        if (Files.exists(guExe) && !Files.exists(nativeImageExe)) {
+            ProcessBuilder processBuilder = new ProcessBuilder(guExe.toString(), "install", "native-image");
+            processBuilder.inheritIO();
+            try {
+                Process nativeImageFetchingProcess = processBuilder.start();
+                if (nativeImageFetchingProcess.waitFor() != 0) {
+                    throw new MojoExecutionException("native-image was not found, and '" + GU_EXE + "' tool failed to install it.");
                 }
-            } else if (failFast) {
-                throw new MojoExecutionException("'" + GU_EXE + "' tool was not found in your " + javaHomeVariable + "." +
-                        "This probably means that the JDK at '" + graalHomePath + "' is not a GraalVM distribution.");
+            } catch (MojoExecutionException | IOException | InterruptedException e) {
+                throw new MojoExecutionException("Determining GraalVM installation failed with message: " + e.getMessage());
             }
         }
 
         if (!Files.exists(nativeImageExe)) {
             if (failFast) {
-                throw new RuntimeException("native-image is not installed in your " + javaHomeVariable + "." +
-                        "This probably means that the JDK at '" + graalHomePath + "' is not a GraalVM distribution.");
+                throw new MojoExecutionException("native-image is not installed in your " + javaHomeVariable + "." +
+                        "This probably means that the JDK at '" + graalHomePath + "' is not a GraalVM distribution. " +
+                        "The GraalVM Native Maven Plugin requires GRAALVM_HOME or JAVA_HOME to be a GraalVM distribution.");
             } else {
                 return null;
             }
         }
+
         logger.info("Found GraalVM installation from " + javaHomeVariable + " variable.");
         return nativeImageExe;
     }