Simplify running NQP code from Java.

This adds two 'run' methods to the EvalServer which lets us use the EvalServer
from any Java application.

src/vm/jvm/runtime/org/perl6/nqp/tools/EvalServer.java

@@ -1,6 +1,7 @@
 package org.perl6.nqp.tools;
 
 import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.PrintStream;
 import java.net.InetSocketAddress;
@@ -37,6 +38,40 @@ public class EvalServer {
     private WritableByteChannel tokenCh;
     private Path tokenPath;
 
+    public String run(String appPath, String code) throws Exception {
+        String[] argv = new String[2];
+        argv[0] = "-e";
+        argv[1] = code;
+        return run(appPath, argv);
+    }
+
+    public String run(String appPath, String[] argv) throws Exception {
+        try {
+            cuType = LibraryLoader.loadFile( appPath, true );
+        } catch (ThreadDeath td) {
+            throw new RuntimeException("Couldn't loadFile. Your CLASSPATH might not be set up correctly.");
+        }
+
+        GlobalContext gc = new GlobalContext();
+        gc.in = new ByteArrayInputStream(new byte[0]);
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        gc.out = gc.err = new PrintStream( baos, true, "UTF-8" );
+        gc.interceptExit = true;
+        gc.sharingHint = true;
+
+        CompilationUnit cu = CompilationUnit.setupCompilationUnit(gc.mainThread, cuType, true);
+        CodeRef entryRef = null;
+        if (cu.entryQbid() >= 0) entryRef = cu.lookupCodeRef(cu.entryQbid());
+        if (entryRef == null)
+            throw new RuntimeException("This class is not an entry point");
+        try {
+            Ops.invokeMain(gc.mainThread, entryRef, cuType.getName(), argv);
+        } catch (ThreadDeath td) {
+            baos.flush();
+        }
+        return baos.toString("UTF-8");
+    }
+
     public static void main(String[] args) throws Exception {
         String executableName = System.getProperty("perl6.execname");
         if (executableName != null) {