Run Java Applications in Eclipse

Launch Java applications using Eclipse's launch infrastructure. Applications run inside Eclipse with full classpath resolution.

Tools

• runJavaApplication — Launch a Java app in run mode.

  • projectName — Eclipse project name
  • mainClass — Fully qualified main class (e.g., com.example.Main)
  • programArgs — Optional program arguments
  • vmArgs — Optional JVM arguments (e.g., -Xmx512m -Dfoo=bar)
  • timeout — Seconds to wait for completion. 0 = launch in background without waiting. Default: 30

• launchConfiguration — Launch an existing saved launch configuration by name, exactly as it would run from the Run/Debug Configurations dialog. Reuses the configuration's full setup (classpath, VM args, environment variables, working directory, JRebel/agent settings) instead of building a throwaway one.

  • configurationName — Exact name of the saved configuration (use listLaunchConfigurations to find it)
  • mode — run or debug. Default: run
  • timeout — Seconds to wait for completion. 0 = background. Default: 0

• listLaunchConfigurations — List saved launch configurations (name, type, and project/main class for Java apps). Use this to discover the exact name for launchConfiguration.

• stopApplication — Terminate a running application by name/class substring match.

  • nameOrClass — Substring to match (case-insensitive) against launch name or main class

• listActiveLaunches — Show all currently running/debugging sessions with status.

• getConsoleOutput — Read output from Eclipse consoles (use after background launches).

Examples

Run and capture output:

runJavaApplication(projectName="myapp", mainClass="com.example.Main", timeout="30")

Run in background:

runJavaApplication(projectName="myapp", mainClass="com.example.Server", timeout="0")

Run with arguments:

runJavaApplication(projectName="myapp", mainClass="com.example.CLI", programArgs="--verbose input.txt", vmArgs="-Xmx1g")

Launch an existing saved configuration (preserves its env vars, VM args, JRebel, etc.):

listLaunchConfigurations()
launchConfiguration(configurationName="Run Snapshot App No Data Compass Local", mode="debug", timeout="0")

Stop a running app:

stopApplication(nameOrClass="Main")

Notes

• When timeout > 0, the tool waits and returns stdout/stderr and exit code
• When timeout = 0, the app runs in background — use getConsoleOutput to see output and stopApplication to terminate
• Output is truncated at 5000 chars (stdout) / 2000 chars (stderr) to fit context