Print current JVM's Java System Property

It print out all System Properties on console.

package com.devtrigger;

public class SystemProperty {

    public static void main(String... args) {

        System.getProperties().list(System.out);
    }
}

Then you pick up one property which you need and use it.

package com.devtrigger;

public class SystemProperty {

    public static void main(String... args) {

        System.out.println(System.getProperty("user.home"));
        System.out.println(System.getProperty("file.separator"));

...

        // create file object which is under user's home directory
        File file = new File (System.getProperty("user.home") + System.getProperty("file.separator") + "setting.xml");
    }
}

Referred from : System Properties

a Java Class which scans ports in an IP

I had to run port scanner software for security check reason, before deliver the product. I tried to get one utilillity from internet. but, the Websites were blocked in my company to download. so, I just made a Java Class which can do the port scanning. it takes around 20 min to run throught all the ports. If I increase Thread size and shorten the timeout, it will take less then 5 min.

Fornow, I have a little problem. When I let it run quickly, Firewall or security software get activated and deny to response if the port is opened. So, I had to let it run slowly to find all the opened port.

package com.devtrigger;

import java.net.InetSocketAddress;
import java.net.Socket;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;

class PortScanner {

    public static void main(final String... args) throws InterruptedException, ExecutionException {
        final ExecutorService es = Executors.newFixedThreadPool(15);

        final String ip = "127.0.0.1";

        final int timeout = 200;
        final List<Future<ScanResult>> futures = new ArrayList<>();
        for (int port = 1; port <= 65535; port++) {
            futures.add(portIsOpen(es, ip, port, timeout));
        }
        es.awaitTermination(200L, TimeUnit.MILLISECONDS);
        int openPorts = 0;
        for (final Future<ScanResult> f : futures) {
            if (f.get().isOpen()) {
                openPorts++;
                System.out.println(f.get().getPort());
            }
        }
        System.out.println("There are " + openPorts + " open ports on host " + ip + " (probed with a timeout of "
                + timeout + "ms)");
    }

    public static Future<ScanResult> portIsOpen(final ExecutorService es, final String ip, final int port,
            final int timeout) {
        return es.submit(new Callable<ScanResult>() {
            @Override
            public ScanResult call() {
                try {
                    Socket socket = new Socket();
                    socket.connect(new InetSocketAddress(ip, port), timeout);
                    socket.close();
                    return new ScanResult(port, true);
                } catch (Exception ex) {
                    return new ScanResult(port, false);
                }
            }
        });
    }

    public static class ScanResult {
        private int port;

        private boolean isOpen;

        public ScanResult(int port, boolean isOpen) {
            super();
            this.port = port;
            this.isOpen = isOpen;
        }

        public int getPort() {
            return port;
        }

        public void setPort(int port) {
            this.port = port;
        }

        public boolean isOpen() {
            return isOpen;
        }

        public void setOpen(boolean isOpen) {
            this.isOpen = isOpen;
        }

    }
}

How to create and run Apache JMeter Test Scripts from a Java program

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">

 <modelVersion>4.0.0</modelVersion>

 <groupId>myportal</groupId>
 <artifactId>loadtest</artifactId>
 <version>0.0.1-SNAPSHOT</version>
 <packaging>jar</packaging>

 <name>Zug Portal Load Test Tool</name>
 <url>http://maven.apache.org</url>

 <dependencies>
  <dependency>
   <groupId>junit</groupId>
   <artifactId>junit</artifactId>
   <version>4.12</version>
   <scope>test</scope>
  </dependency>
  <dependency>
   <groupId>org.apache.jmeter</groupId>
   <artifactId>ApacheJMeter_http</artifactId>
   <version>2.11</version>
  </dependency>

 </dependencies>
</project>

package myportal.loadtest;

import java.net.URL;

import org.apache.jmeter.control.LoopController;
import org.apache.jmeter.engine.StandardJMeterEngine;
import org.apache.jmeter.protocol.http.sampler.HTTPSampler;
import org.apache.jmeter.testelement.TestElement;
import org.apache.jmeter.testelement.TestPlan;
import org.apache.jmeter.threads.SetupThreadGroup;
import org.apache.jmeter.util.JMeterUtils;
import org.apache.jorphan.collections.HashTree;

public class SampleJmeter {

    public static void main(String[] args) {
        // Engine
        StandardJMeterEngine jm = new StandardJMeterEngine();
        URL property = SampleJmeter.class.getClassLoader().getResource("jmeter.properties");

        // jmeter.properties
        JMeterUtils.loadJMeterProperties(property.getPath());

        HashTree hashTree = new HashTree();

        // HTTP Sampler
        HTTPSampler httpSampler = new HTTPSampler();
        httpSampler.setDomain("www.google.com");
        httpSampler.setPort(80);
        httpSampler.setPath("/");
        httpSampler.setMethod("GET");

        // Loop Controller
        TestElement loopCtrl = new LoopController();
        ((LoopController) loopCtrl).setLoops(1);
        ((LoopController) loopCtrl).addTestElement(httpSampler);
        ((LoopController) loopCtrl).setFirst(true);

        // Thread Group
        SetupThreadGroup threadGroup = new SetupThreadGroup();
        threadGroup.setNumThreads(1);
        threadGroup.setRampUp(1);
        threadGroup.setSamplerController((LoopController) loopCtrl);

        // Test plan
        TestPlan testPlan = new TestPlan("MY TEST PLAN");

        hashTree.add("testPlan", testPlan);
        hashTree.add("loopCtrl", loopCtrl);
        hashTree.add("threadGroup", threadGroup);
        hashTree.add("httpSampler", httpSampler);

        jm.configure(hashTree);

        jm.run();
    }
}

meter.properties file is from the JMeter installation /bin directory.