Nashorn java.lang.NoClassDefFoundError: jdk/nashorn/api/scripting/JSObject - java

I am migrating my Eclipse RCP to use JDK 8 and I heavily use the JS ScriptEngine. Now that Nashorn is introduced I had to add the following line to get the importClass and importPackage functions to work:
load("nashorn:mozilla_compat.js");
After doing so, I got java.lang.NoClassDefFoundError: jdk/nashorn/api/scripting/JSObject.
I am using Nashorn inside an Eclipse RCP. The problem occurs when I call a Java function from the Javascript and try to use the parameter sent. The parameter I want to send is a Javascript function that I would like to execute call on later in the code.
I have the following code:
TestNashorn.java
package com.test.nashorn;
import java.io.FileNotFoundException;
import java.io.FileReader;
import javax.script.Invocable;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;
import javax.script.Invocable;
import jdk.nashorn.api.scripting.JSObject;
public class TestNashorn {
public static void main(String[] args) {
ScriptEngine engine = (new ScriptEngineManager()).getEngineByName("js");
try {
engine.eval(new FileReader("C:/Users/user/workspace_nashorn/TestNashorn/src/com/test/nashorn/test.js"));
Object o = ((Invocable)engine).invokeFunction("generate");
} catch (ScriptException | FileNotFoundException | NoSuchMethodException e) {
e.printStackTrace();
}
}
public static int test(JSObject o1) {
System.out.println(o1.getClass().toString());
JSObject som = ((JSObject)o1);
return 1;
}
}
test.js
load("nashorn:mozilla_compat.js");
importClass(com.test.nashorn.TestNashorn);
function generate()
{
function asd(variablex) { print('Hello, ' + variablex); }
var result = TestNashorn.test(asd);
}
The problem occurs in line JSObject som = ((JSObject)o1);, although I can successfully import jdk.nashorn.api.scripting.JSObject;.
The exception message exactly says:
jdk.nashorn.api.scripting.JSObject cannot be found by com.test.nashorn_1.0.0.qualifier

So.. I got to fix my issue and was able to use JSObject in my code. What I have done was the following:
Added -Dorg.osgi.framework.bundle.parent=ext to myproduct.product file
This added it to the .ini file in my product build which revealed the classes found in Nashorn APIs.

Related

Could not find or load main class FaceDetect in java with angus.ai

I get the following error when I try to run
java -cp 'angus-sdk-java-0.0.2-jar-with-dependencies.jar:.' FaceDetect
I am following a tutorial for face detection in http://angus-doc.readthedocs.io/en/latest/getting-started/java.html . Below is my java code,
import java.io.IOException;
import org.json.simple.JSONObject;
import ai.angus.sdk.Configuration;
import ai.angus.sdk.Job;
import ai.angus.sdk.ProcessException;
import ai.angus.sdk.Root;
import ai.angus.sdk.Service;
import ai.angus.sdk.impl.ConfigurationImpl;
import ai.angus.sdk.impl.File;
public class FaceDetect {
public static void main(String[] args) throws IOException, ProcessException {
Configuration conf = new ConfigurationImpl();
Root root = conf.connect();
Service service = root.getServices().getService("age_and_gender_estimation", 1);
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params.put("image", new File("Downloads/IMG_1060.jpg"));
Job job = service.process(params);
System.out.println(job.getResult().toJSONString());
}
}
I don't understand the problem with it. I have tried all the answers in the stack overflow but nothing is working for me.
remove the single qoutes around the classpath:
java -cp angus-sdk-java-0.0.2-jar-with-dependencies.jar:. FaceDetect

While creating this java program in oracle db. Im facing some errors. CAn anyone tell me the way to compile it. the code is as follows

Below code is working properly in eclipse. But I,m trying to create this source in oracle 11g Db. While creating it throws some warnings.
create or replace
and compile java source named "Noitime"
as
package com;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.attribute.FileTime;
public class Noitime {
public String attr(String filepath,String filename)
{
long time = System.currentTimeMillis();
FileTime fileTime = FileTime.fromMillis(time);
Path path = Paths.get(filepath,filename);
try {
Files.setLastModifiedTime(path, fileTime);
return "Success";
} catch (IOException e) {
System.err.println(e);
return "Fail";
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}
}
You appear to have garbled the error/warning message, but I think that it is telling you that you should be using the pathname "com/Noitime.java" when compiling. The pathname you use should correspond to the full class name, and the full class name is "com.Noitime".

Rserve - Eclipse & Java

Hi I am setting up rserve based on the instructions on this website.
http://www.codophile.com/how-to-integrate-r-with-java-using-rserve/
However in eclipse I am getting an error when using 'eval'
double d[] = c.eval("rnorm(10)").asDoubles();
error - 'The method eval(String) is undefined for the type RConnection'
The JARS have been correctly loaded into the build path and rserve is running, however I cannot figure out why only the eval function is causing an issue.
In addition to this the import of ...
import org.rosuda.REngine.Rserve.RConnection;
causes an error - 'The import org.rosuda.REngine.Rserve.RConnection conflicts with a type defined in the same file'
does anyone have any idea why this is the case? Thanks
all imports :
import org.rosuda.REngine.REXPMismatchException;
import org.rosuda.REngine.Rserve.RConnection;
import org.rosuda.REngine.Rserve.RserveException;
public class RConnection {
public int[] mean(String a[]) {
setupR();
return null;
}
public void setupR(){
try {
/* Create a connection to Rserve instance running
* on default port 6311
*/
RConnection c = new RConnection();// make a new local connection on default port (6311)
double d[] = c.eval("rnorm(10)").asDoubles();
org.rosuda.REngine.REXP x0 = c.eval("R.version.string");
System.out.println(x0.asString());
} catch (RserveException e) {
e.printStackTrace();
} catch (REXPMismatchException e) {
e.printStackTrace();
}
}
}
By using import org.rosuda.REngine.Rserve.RConnection; you are tying to make RConnection known in the local namespace.
However, you already defined a class called RConnection locally.
Please rename your class RConnection, and you should be able to import org.rosuda.REngine.Rserve.RConnection.

Error in HTTPUnit Code

I am trying to learn HTTPUnit and have read cookbook mentioned on http://httpunit.sourceforge.net/doc/cookbook.html
But when I am trying this very simple code
package httpUnit.test;
import java.io.IOException;
import org.xml.sax.SAXException;
import com.meterware.httpunit.GetMethodWebRequest;
import com.meterware.httpunit.WebConversation;
import com.meterware.httpunit.WebLink;
import com.meterware.httpunit.WebRequest;
import com.meterware.httpunit.WebResponse;
/*** Hello world!**/
public class App{
public static void main( String[] args ) throws IOException, SAXException {
System.out.println( "Trying HTPUnit library");
WebConversation wc = new WebConversation();
WebRequest req = new GetMethodWebRequest("http://localhost:8080/proof/demo.html");
WebResponse resp = wc.getResponse(req);
/* WebLink[ ] link = resp.getLinks();
for (int i=0; i<link.length; i++) {
System.out.println(link[i].getText());
}
System.out.println(link.length);
*/
}
};
I am getting the following errors:
TypeError: undefined is not a function. (httpunit; line 15)
at org.mozilla.javascript.NativeGlobal.constructError(NativeGlobal.java:597)
at org.mozilla.javascript.NativeGlobal.constructError(NativeGlobal.java:557)
Error continues.....
and
Exception in thread "main" com.meterware.httpunit.ScriptException: Script '/*!
* jQuery JavaScript Library v1.6
* http://jquery.com/
Can somebody please figure out what could be the problem. I could not understand. I have created the maven project with maven dependency from http://mvnrepository.com/artifact/httpunit/httpunit/1.6.1
And I have hosted demo.html in proof folder in tomcat which is opening fine in browser.
I think the problem is with javascript only.
Checkout http://httpunit.sourceforge.net/doc/faq.html#javascript
And use HttpUnitOptions.setScriptingEnabled(false);
I think it will do.

Java Scripting Engine importing my classes does not work

A code is worth 1000 words of explaining it :-)
package jasim;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;
public class JSTest {
public static void main(String[] args) throws ScriptException {
ScriptEngine jse = new ScriptEngineManager().getEngineByExtension("js");
jse.eval("println(new jasim.JSTest().toString)");
}
#Override
public String toString() {
return "JSTest Object";
}
}
This code will fail with the below exception:
Exception in thread "main" javax.script.ScriptException: sun.org.mozilla.javascript.internal.EcmaError: ReferenceError: "jasim" is not defined. (<Unknown source>#1) in <Unknown source> at line number 1
How do I import my own classes into the ScriptEngine?
After looking at the Mozilla Rhino docs, the solution is either to use:
importPackage(Packages.jasim) within the script, or to use new Packages.jasim.JSTest()
This is not so clear in the Sun docs regarding the importPackage in the ScriptingEngine docs.
The same way you import javax.script.ScriptEngine;...
Just make sure your classes are in the CLASSPATH

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