how to run code compiled by JavaCompiler?
Is there any way to run program compiled by JavaCompiler? [javax.tools.JavaCompiler]
My code:
JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
DiagnosticCollector<JavaFileObject> diagnostics = new DiagnosticCollector<JavaFileObject>();
CompilationTask task = compiler.getTask(null, null, diagnostics, null, null, prepareFile(nazwa, content));
task.call();
List<String> returnErrors = new ArrayList<String开发者_运维百科>();
String tmp = new String();
for (Diagnostic diagnostic : diagnostics.getDiagnostics()) {
tmp = String.valueOf(diagnostic.getLineNumber());
tmp += " msg: "+ diagnostic.getMessage(null);
returnErrors.add(tmp.replaceAll("\n", " "));
}
Now i want to run that program with lifetime 1 sec and get output to string variable. Is there any way i could do that?
You need to use reflection, something like that:
// Obtain a class loader for the compiled classes
ClassLoader cl = fileManager.getClassLoader(CLASS_OUTPUT);
// Load the compiled class
Class compiledClass = cl.loadClass(CLASS_NAME);
// Find the eval method
Method myMethod = compiledClass.getMethod("myMethod");
// Invoke it
return myMethod.invoke(null);
Adapt it of course to suit your needs
You have to add the compiled class to the current classpath.
There's a number of ways to do that, depending on how your project is set up. Here's one instance using java.net.URLClassLoader:
ClassLoader cl_old = Thread.currentThread().getContextClassLoader();
ClassLoader cl_new = new URLClassLoader(urls.toArray(new URL[0]), cl_old);
where "urls" is a list of urls pointing to the filesystem.
精彩评论