io.github.stylesmile.server.MethodContextHandler Maven / Gradle / Ivy
package io.github.stylesmile.server;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
/**
* The {@code MethodContextHandler} services a context
* by invoking a handler method on a specified object.
*
* The method must have the same signature and contract as
* {@link ContextHandler#serve}, but can have an arbitrary name.
*
* @see JdkHTTPServer.VirtualHost#addContexts(Object)
*/
public class MethodContextHandler implements ContextHandler {
protected final Method m;
protected final Object obj;
public MethodContextHandler(Method m, Object obj) throws IllegalArgumentException {
this.m = m;
this.obj = obj;
Class[] params = m.getParameterTypes();
if (params.length != 2
|| !Request.class.isAssignableFrom(params[0])
|| !Response.class.isAssignableFrom(params[1])
|| !int.class.isAssignableFrom(m.getReturnType())) {
throw new IllegalArgumentException("invalid method signature: " + m);
}
}
public int serve(Request req, Response resp) throws IOException {
try {
m.setAccessible(true);
return (Integer) m.invoke(obj, req, resp);
} catch (InvocationTargetException ite) {
throw new IOException("error: " + ite.getCause().getMessage());
} catch (Exception e) {
throw new IOException("error: " + e);
}
}
}