{"record":{"id":"45e96c9be24d2733","repo":"slint-ui/slint","slug":"could-not-run-the-java-compiler-e","errorCode":null,"errorMessage":"Could not run the java compiler: {e}","messagePattern":"Could not run the java compiler: (.+?)","errorType":"panic","errorClass":null,"httpStatus":null,"severity":"error","filePath":"internal/backends/android-activity/build.rs","lineNumber":52,"sourceCode":"    let android_jar = android_build::android_jar(None).expect(\"No Android platforms found\");\n\n    // Compile the Java file into .class files\n    let o = JavaBuild::new()\n        .file(&java_src_path)\n        .class_path(&android_jar)\n        .classes_out_dir(&out_class_dir)\n        .java_source_version(8)\n        .java_target_version(8)\n        .debug_info(android_build::DebugInfo {\n            line_numbers: !release_mode,\n            variables: !release_mode,\n            source_files: !release_mode,\n        })\n        .command()\n        .unwrap_or_else(|e| panic!(\"Could not generate the java compiler command: {e}\"))\n        .args([\"-encoding\", \"UTF-8\"])\n        .output()\n        .unwrap_or_else(|e| panic!(\"Could not run the java compiler: {e}\"));\n\n    if !o.status.success() {\n        panic!(\"Java compilation failed: {}\", String::from_utf8_lossy(&o.stderr));\n    }\n\n    let o = Dexer::new()\n        .android_jar(&android_jar)\n        .class_path(&out_class_dir)\n        .collect_classes(&out_class_dir)\n        .unwrap()\n        .release(release_mode)\n        .android_min_api(20) // disable multidex for single dex file output\n        .out_dir(out_dir)\n        .command()\n        .unwrap_or_else(|e| panic!(\"Could not generate the D8 command: {e}\"))\n        .output()\n        .unwrap_or_else(|e| panic!(\"Error running D8: {e}\"));\n","sourceCodeStart":34,"sourceCodeEnd":70,"githubUrl":"https://github.com/slint-ui/slint/blob/bb937076de3f7919766c1f25e2e969367cf77e9a/internal/backends/android-activity/build.rs#L34-L70","documentation":"The javac command was constructed but executing it (via `.output()`) failed, meaning the process could not be spawned or run to completion. The build script panics with this message, distinguishing an execution failure (e.g. javac binary vanished, exec permission, IO error) from a compilation error (error 39).","triggerScenarios":"`Command::output()` on the javac command returns Err — javac not executable, binary removed between discovery and spawn, OOM-killer or IO failure during execution.","commonSituations":"Partially installed or broken JDK; environment sanitization removing PATH to the tool binary; resource limits (ulimit, cgroup OOM) killing process spawn in CI.","solutions":["Confirm javac at the resolved path is executable (`ls -l $(command -v javac)`, chmod +x if needed)","Reinstall/repair the JDK if the binary is missing or corrupted","Raise process/memory limits in the CI environment if spawn fails from resource exhaustion","Run the same javac command manually to see the underlying OS error"],"exampleFix":"// before\njavac: Permission denied\n// after\nchmod +x $JAVA_HOME/bin/javac && cargo build","handlingStrategy":"validation","validationCode":"import subprocess, shutil\njavac = shutil.which(\"javac\")\nassert javac and os.access(javac, os.X_OK), \"javac missing or not executable\"\nsubprocess.run([javac, \"-version\"], check=True, capture_output=True)","typeGuard":null,"tryCatchPattern":null,"preventionTips":["Confirm javac is executable after JDK installation","Avoid over-restrictive sandbox/ulimit settings in CI","Repair broken JDK installs rather than working around them"],"tags":["android","java","build-script","process-execution"],"backgroundTag":"command-not-found","analyzedSha":"bb937076de3f7919766c1f25e2e969367cf77e9a","analyzedAt":"2026-09-16T01:37:20.251Z","contentChangedAt":"2026-09-16T01:37:20.251Z","schemaVersion":2},"datasetVersion":"2026-09-23T08:17:48.524Z"}