Print user friendly error when starting Cypher Shell in unsupported jvm

Build Cypher Shell as a multi release jar. Starting with an old jvm version
prints a more user friendly error message, instead of failing with the cryptic
`Unrecognized option: --add-opens`.

community/cypher-shell/cypher-shell/pom.xml

@@ -157,6 +157,49 @@
         </resources>
 
         <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <executions>
+                    <!-- The purpose of this execution is to provide a user-friendly error message when started with an unsupported jvm -->
+                    <execution>
+                        <id>compile-java7</id>
+                        <goals>
+                            <goal>compile</goal>
+                        </goals>
+                        <configuration>
+                            <source>1.7</source>
+                            <target>1.7</target>
+                            <compileSourceRoots>
+                                <compileSourceRoot>${project.basedir}/src/main/java7</compileSourceRoot>
+                            </compileSourceRoots>
+                        </configuration>
+                    </execution>
+                    <!-- This is the normal execution -->
+                    <execution>
+                        <id>compile</id>
+                        <phase>compile</phase>
+                        <goals>
+                            <goal>compile</goal>
+                        </goals>
+                        <configuration>
+                            <release>${maven.compiler.target}</release>
+                            <multiReleaseOutput>true</multiReleaseOutput>
+                        </configuration>
+                    </execution>
+                </executions>
+            </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-jar-plugin</artifactId>
+                <configuration>
+                    <archive>
+                        <manifestEntries>
+                            <Multi-Release>true</Multi-Release>
+                        </manifestEntries>
+                    </archive>
+                </configuration>
+            </plugin>
             <plugin>
                 <groupId>org.codehaus.mojo</groupId>
                 <artifactId>appassembler-maven-plugin</artifactId>
@@ -165,14 +208,9 @@
                     <assembleDirectory>${project.build.directory}/assembly</assembleDirectory>
                     <repositoryLayout>flat</repositoryLayout>
                     <repositoryName>lib</repositoryName>
-                    <extraJvmArguments>
-                        --add-opens java.base/java.net=ALL-UNNAMED
-                        --add-opens java.base/java.lang=ALL-UNNAMED
-                        --add-opens=java.base/java.nio=ALL-UNNAMED
-                    </extraJvmArguments>
                     <programs>
                         <program>
-                            <mainClass>${name-of-main-class}</mainClass>
+                            <mainClass>org.neo4j.shell.startup.CypherShellBoot</mainClass>
                             <id>cypher-shell</id>
                         </program>
                     </programs>

community/cypher-shell/cypher-shell/src/main/java/org/neo4j/shell/startup/CypherShellBoot.java

+/*
+ * Copyright (c) "Neo4j"
+ * Neo4j Sweden AB [http://neo4j.com]
+ *
+ * This file is part of Neo4j.
+ *
+ * Neo4j is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.neo4j.shell.startup;
+
+import java.io.File;
+import java.io.IOException;
+import java.lang.management.ManagementFactory;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Map;
+import org.neo4j.shell.Main;
+
+public class CypherShellBoot {
+
+    /**
+     * IMPORTANT NOTE!
+     * The only purpose of this class is just to forward to the actual main. Its part of a multi-version jar
+     * to be able to provide a useful error message when used on an old and unsupported version of java.
+     */
+    public static void main(String[] args) throws IOException, InterruptedException {
+        jvmCheck();
+
+        final var processBuilder = new ProcessBuilder(command(args));
+        processBuilder.inheritIO();
+        processBuilder.environment().putAll(environment());
+
+        Process process = null;
+        int exitCode;
+        try {
+            process = processBuilder.start();
+            exitCode = process.waitFor();
+        } catch (Exception e) {
+            if (process != null) {
+                process.destroy();
+            }
+            throw e;
+        }
+
+        System.exit(exitCode);
+    }
+
+    private static void jvmCheck() {
+        if (Runtime.version().feature() < 17) {
+            System.err.println(
+                    "You are using an unsupported version of the Java runtime. Please use Oracle(R) Java(TM) 17 or OpenJDK(TM) 17.");
+        }
+    }
+
+    private static List<String> command(String[] args) {
+        final String javaCommand = ProcessHandle.current()
+                .info()
+                .command()
+                .orElseThrow(() -> new IllegalStateException("Wasn't able to figure out java binary"));
+        // The `app.home` property is set by the appassembler-maven-plugin
+        final String classPath = System.getProperty("app.home") + File.separator + "lib" + File.separator + "*";
+
+        final var command = new ArrayList<String>();
+        command.add(javaCommand);
+        command.addAll(jvmInputArguments());
+        command.add("-cp");
+        command.add(classPath);
+        command.add(Main.class.getName());
+        command.addAll(Arrays.asList(args));
+
+        return command;
+    }
+
+    private static Map<String, String> environment() {
+        if (System.getenv() == null) {
+            return Map.of();
+        }
+        return System.getenv();
+    }
+
+    private static List<String> jvmInputArguments() {
+        final var arguments = new ArrayList<String>();
+        arguments.addAll(ManagementFactory.getRuntimeMXBean().getInputArguments());
+        arguments.addAll(extraJvmArguments());
+        return arguments;
+    }
+
+    private static List<String> extraJvmArguments() {
+        return List.of(
+                "--add-opens", "java.base/java.net=ALL-UNNAMED",
+                "--add-opens", "java.base/java.lang=ALL-UNNAMED",
+                "--add-opens", "java.base/java.nio=ALL-UNNAMED");
+    }
+}

community/cypher-shell/cypher-shell/src/main/java7/org/neo4j/shell/startup/CypherShellBoot.java

+/*
+ * Copyright (c) "Neo4j"
+ * Neo4j Sweden AB [http://neo4j.com]
+ *
+ * This file is part of Neo4j.
+ *
+ * Neo4j is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.neo4j.shell.startup;
+
+public class CypherShellBoot {
+
+    /**
+     * IMPORTANT NOTE!
+     * This class is compiled using Java 7 and can not use any dependencies or include any other classes.
+     * Its only purpose is to print a useful error message when Cypher Shell is started using an old, unsupported java.
+     */
+    public static void main(String[] args) {
+        printJavaVersionErrorMessage();
+    }
+
+    static void printJavaVersionErrorMessage() {
+        String version = System.getProperty("java.version");
+        System.out.println("Unsupported Java " + version
+                + " detected. Please use Oracle(R) Java(TM) 17, OpenJDK(TM) 17 to run Cypher Shell.");
+    }
+}

community/cypher-shell/integration-test/pom.xml

@@ -76,6 +76,16 @@
             <type>test-jar</type>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>commons-io</groupId>
+            <artifactId>commons-io</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.commons</groupId>
+            <artifactId>commons-compress</artifactId>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <profiles>

community/cypher-shell/integration-test/src/test/java/org/neo4j/shell/BinaryNonInteractiveIntegrationTest.java

+/*
+ * Copyright (c) "Neo4j"
+ * Neo4j Sweden AB [http://neo4j.com]
+ *
+ * This file is part of Neo4j.
+ *
+ * Neo4j is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.neo4j.shell;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.startsWith;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.io.File;
+import java.nio.charset.Charset;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.StandardOpenOption;
+import java.util.Arrays;
+import java.util.List;
+import java.util.function.Supplier;
+import org.apache.commons.io.IOUtils;
+import org.eclipse.collections.api.factory.Lists;
+import org.eclipse.collections.api.list.MutableList;
+import org.hamcrest.Matcher;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+
+public class BinaryNonInteractiveIntegrationTest {
+    private static final String USER = "neo4j";
+    private static final String PASSWORD = "neo";
+
+    @TempDir
+    Path tempDir;
+
+    private File cypherShellBinary = cypherShellBinary();
+
+    @Test
+    void simpleReturn() {
+        assertOutput(defaultArgsWith(), "return 1 as result;", equalTo("result\n1\n"));
+    }
+
+    @Test
+    void simpleReturnVerbose() {
+        assertOutput(
+                defaultArgsWith("--format", "verbose"),
+                "return 1 as result;",
+                startsWith(
+                        """
+                +--------+
+                | result |
+                +--------+
+                | 1      |
+                +--------+
+
+                1 row
+                ready to start consuming query after"""));
+    }
+
+    private static MutableList<String> defaultArgsWith(String... args) {
+        return Lists.mutable
+                .with("-u", USER, "-p", PASSWORD, "--non-interactive")
+                .withAll(Arrays.asList(args));
+    }
+
+    private void assertOutput(List<String> args, String input, Matcher<String> expectedOutput) {
+        final var command =
+                Lists.mutable.with(cypherShellBinary.getAbsolutePath()).withAll(args);
+        final var result = execute(command, input);
+
+        assertEquals(0, result.exitCode(), failureMessage(result));
+        assertThat(result.out(), expectedOutput);
+        assertEquals("", result.err());
+    }
+
+    private Supplier<String> failureMessage(ProcessExecution result) {
+        return () -> "\nFailure executing: " + String.join(" ", result.command()) + "\n" + "Exit code:"
+                + result.exitCode() + "\n" + "Output:\n"
+                + result.out()
+                + "\n\n" + "Error output:\n"
+                + result.err()
+                + "\n\n";
+    }
+
+    private ProcessExecution execute(List<String> command, String input) {
+        Path inFile = tempDir.resolve("input.txt");
+
+        Process process = null;
+        try {
+            Files.write(inFile, input.getBytes(), StandardOpenOption.CREATE_NEW);
+
+            process = new ProcessBuilder(command).redirectInput(inFile.toFile()).start();
+
+            final var out = IOUtils.toString(process.getInputStream(), Charset.defaultCharset());
+            final var err = IOUtils.toString(process.getErrorStream(), Charset.defaultCharset());
+
+            int exitCode = process.waitFor();
+
+            return new ProcessExecution(command, out, err, exitCode);
+        } catch (Exception e) {
+            if (process != null) {
+                process.destroy();
+            }
+            throw new RuntimeException("Failed to run: " + String.join(" ", command), e);
+        }
+    }
+
+    public static File cypherShellBinary() {
+        // TODO Test using the binary extracted from the zip distribution instead
+        // TODO Also test native binaries
+        if (System.getProperty("os.name").startsWith("Windows")) {
+            return new File("../cypher-shell/target/assembly/bin/cypher-shell.bat");
+        }
+        return new File("../cypher-shell/target/assembly/bin/cypher-shell");
+    }
+}
+
+record ProcessExecution(List<String> command, String out, String err, int exitCode) {}

community/cypher-shell/integration-test/src/test/java/org/neo4j/shell/MainIntegrationTest.java

@@ -69,6 +69,7 @@ import org.neo4j.shell.test.AssertableMain;
 import org.neo4j.shell.util.Version;
 import org.neo4j.shell.util.Versions;
 
+// NOTE! Consider adding tests to BinaryNonInteractiveIntegrationTest instead of here.
 @Timeout(value = 5, unit = MINUTES)
 class MainIntegrationTest {
     private static final String USER = "neo4j";