What causes "No JDK specified" in JetBrains/intellij-community?

Open File | Project Structure | Project (and Modules) and set a valid Project/Module SDK

JetBrains/intellij-community · error · ExecutionException

No JDK specified

Error message

No JDK specified

What it means

In appendForkInfo, after fork-mode checks pass, the state computes JavaParameters and requires javaParameters.getJdk() to be non-null; when the run configuration resolved to no JDK/Sdk, an ExecutionException('No JDK specified') is thrown and the run stops before any process starts.

Source

Thrown at java/execution/impl/src/com/intellij/execution/JavaTestFrameworkRunnableState.java:479

          final String actionName = executor.getActionName();
          throw new CantRunException(JavaCompilerBundle.message("action.disabled.when.per.module.working.directory.configured",
                                                                actionName));
        }
      }
      else {
        return;
      }
    }
    else if (isExecutorDisabledInForkedMode()) {
      final String actionName = executor.getActionName();
      throw new CantRunException(JavaCompilerBundle.message("action.disabled.in.fork.mode", actionName,
                                                            StringUtil.toLowerCase(actionName)));
    }

    final JavaParameters javaParameters = getJavaParameters();
    final Sdk jdk = javaParameters.getJdk();
    if (jdk == null) {
      throw new ExecutionException(ExecutionBundle.message("run.configuration.error.no.jdk.specified"));
    }

    try {
      final File tempFile = FileUtil.createTempFile("command.line", "", true);
      try (PrintWriter writer = new PrintWriter(tempFile, StandardCharsets.UTF_8)) {
        ShortenCommandLine shortenCommandLine = getConfiguration().getShortenCommandLine();
        boolean useDynamicClasspathForForkMode = shortenCommandLine == null
                                                 ? JdkUtil.useDynamicClasspath(getConfiguration().getProject())
                                                 : shortenCommandLine != ShortenCommandLine.NONE;
        if (shortenCommandLine == ShortenCommandLine.ARGS_FILE) {
          //see com.intellij.rt.execution.testFrameworks.ForkedByModuleSplitter.startChildFork
          writer.println(shortenCommandLine);
        }
        else if (useDynamicClasspathForForkMode && forkPerModule()) {
          writer.println("use classpath jar");
        }
        else {
          writer.println("");

View on GitHub (pinned to be881553f2)

Solutions

Open File | Project Structure | Project (and Modules) and set a valid Project/Module SDK
If the run configuration specifies an 'Alternative JRE' / JRE path, fix it to an existing JDK installation
Re-import/refresh the project (Maven/Gradle sync) so SDK references resolve
Verify the JDK path exists on disk (java -version via that home) — on CI, ensure the JDK is installed and the path matches

Defensive patterns

Strategy: validation

Validate before calling

// verify a JDK resolves before building the command line
Sdk jdk = javaParameters.getJdk();
if (jdk == null || jdk.getHomePath() == null || !new File(jdk.getHomePath()).isDirectory()) {
  throw new ConfigurationError("Configure a valid Project/Module SDK");
}

Try / catch

try {
  state.appendForkInfo(executor);
} catch (ExecutionException e) {
  if (ExecutionBundle.message("run.configuration.error.no.jdk.specified").equals(e.getMessage())) {
    promptToConfigureSdk();
  }
}

Prevention

Keep Project SDK pointing at an existing JDK home; update it after JDK upgrades
On CI, verify JAVA_HOME / configured SDK path before launching tests
If using 'Alternative JRE' in a config, validate the path still exists

When it happens

Trigger: JavaParameters produced by the test run configuration have a null JDK: project SDK removed/renamed, module SDK invalid, JRE path pointing to a deleted JDK home, or a runner that never set the JDK (e.g. JPS build not yet run, or dependency resolution failed).

Common situations: SDK defined by path that no longer exists (moved/updated JDK), project SDK set to 'No SDK' after import, module inherited SDK removed, or CI machines lacking the configured JDK. Also when the JdkSelector cannot map the chosen 'Alternative JRE' path.

Related errors

AI-assisted analysis of JetBrains/intellij-community@be881553f2 (2026-08-14). Data as JSON: /api/errors/f112b984651ba0e2. Report an issue: GitHub.