Launch browser automatically after spring-boot webapp is ready - spring

How do I launch a browser automatically after starting the spring boot application.Is there any listener method callback to check if the webapp has been deployed and is ready to serve the requests,so that when the browser is loaded , the user sees the index page and can start interacting with the webapp?
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
// launch browser on localhost
}

Below code worked for me:
#EventListener({ApplicationReadyEvent.class})
void applicationReadyEvent() {
System.out.println("Application started ... launching browser now");
browse("www.google.com");
}
public static void browse(String url) {
if(Desktop.isDesktopSupported()){
Desktop desktop = Desktop.getDesktop();
try {
desktop.browse(new URI(url));
} catch (IOException | URISyntaxException e) {
e.printStackTrace();
}
}else{
Runtime runtime = Runtime.getRuntime();
try {
runtime.exec("rundll32 url.dll,FileProtocolHandler " + url);
} catch (IOException e) {
e.printStackTrace();
}
}
}

#SpringBootApplication
#ComponentScan(basePackageClasses = com.io.controller.HelloController.class)
public class HectorApplication {
public static void main(String[] args) throws IOException {
SpringApplication.run(HectorApplication.class, args);
openHomePage();
}
private static void openHomePage() throws IOException {
Runtime rt = Runtime.getRuntime();
rt.exec("rundll32 url.dll,FileProtocolHandler " + "http://localhost:8080");
}
}

You could do it by some java code. I am not sure if spring boot has something out of the box.
import java.awt.Desktop;
import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;
public class Browser {
public static void main(String[] args) {
String url = "http://www.google.com";
if(Desktop.isDesktopSupported()){
Desktop desktop = Desktop.getDesktop();
try {
desktop.browse(new URI(url));
} catch (IOException | URISyntaxException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}else{
Runtime runtime = Runtime.getRuntime();
try {
runtime.exec("xdg-open " + url);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}

I've recently been attempting to get this working myself, I know it's been a while since this question was asked but my working (and very basic/simple) solution is shown below. This is a starting point for anyone wanting to get this working, refactor as required in your app!
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import java.awt.*;
import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;
#SpringBootApplication
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
openHomePage();
}
private static void openHomePage() {
try {
URI homepage = new URI("http://localhost:8080/");
Desktop.getDesktop().browse(homepage);
} catch (URISyntaxException | IOException e) {
e.printStackTrace();
}
}
}

If you package the application as a WAR file, configure an application server, like Tomcat, and restart the configured application server through your IDE, IDEs can automatically open a browser-tab.
If you want to package your application as a JAR file, your IDE will not be able to open a web browser, so you have to open a web browser and type the desired link(localhost:8080). But in the developing phase, taking these boring steps might be very tedious.
It is possible to open a browser with Java programming language after the spring-boot application gets ready. You can use the third-party library like Selenium or use the following code snippet.
The code snippet to open a browser
#EventListener({ApplicationReadyEvent.class})
private void applicationReadyEvent()
{
if (Desktop.isDesktopSupported())
{
Desktop desktop = Desktop.getDesktop();
try
{
desktop.browse(new URI(url));
} catch (IOException | URISyntaxException e)
{
e.printStackTrace();
}
} else
{
Runtime runtime = Runtime.getRuntime();
String[] command;
String operatingSystemName = System.getProperty("os.name").toLowerCase();
if (operatingSystemName.indexOf("nix") >= 0 || operatingSystemName.indexOf("nux") >= 0)
{
String[] browsers = {"opera", "google-chrome", "epiphany", "firefox", "mozilla", "konqueror", "netscape", "links", "lynx"};
StringBuffer stringBuffer = new StringBuffer();
for (int i = 0; i < browsers.length; i++)
{
if (i == 0) stringBuffer.append(String.format("%s \"%s\"", browsers[i], url));
else stringBuffer.append(String.format(" || %s \"%s\"", browsers[i], url));
}
command = new String[]{"sh", "-c", stringBuffer.toString()};
} else if (operatingSystemName.indexOf("win") >= 0)
{
command = new String[]{"rundll32 url.dll,FileProtocolHandler " + url};
} else if (operatingSystemName.indexOf("mac") >= 0)
{
command = new String[]{"open " + url};
} else
{
System.out.println("an unknown operating system!!");
return;
}
try
{
if (command.length > 1) runtime.exec(command); // linux
else runtime.exec(command[0]); // windows or mac
} catch (IOException e)
{
e.printStackTrace();
}
}
}
Using Selenium to open a browser
To use the selenium library add the following dependency to your pom.xml file.
<dependency>
<groupId>org.seleniumhq.selenium</groupId>
<artifactId>selenium-java</artifactId>
<version>3.141.59</version>
</dependency>
Then in your main class, add the following code snippet.
#EventListener({ApplicationReadyEvent.class})
private void applicationReadyEvent()
{
String url = "http://localhost:8080";
// pointing to the download driver
System.setProperty("webdriver.chrome.driver", "Downloaded-PATH/chromedriver");
ChromeDriver chromeDriver = new ChromeDriver();
chromeDriver.get(url);
}
Notice: It is possible to use most of the popular browsers like FirefoxDriver, OperaDriver, EdgeDriver, but it is necessary to download browsers' drivers beforehand.

Runtime rt = Runtime.getRuntime();
try {
rt.exec("cmd /c start chrome.exe https://localhost:8080");
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
The code above worked for me. Change chrome.exe to the browser of your choice and Url to to your choice.
Note: You must include the scheme - http or https, and the browser you choose must me installed, else your app will run without opening the browser automatically.
Works only for windows though.

Related

How to run Quarkus programatically in Test mode

I am trying to run acceptance tests with concordion fixtures in a quarkus project. Concordion does not work with Junit5 so I am using its original #Run(ConcordionRunner.class).
I am creating a superclass to start my quarkus application before tests like that:
#RunWith(ConcordionRunner.class)
public abstract class AbstractFixture {
public static RunningQuarkusApplication application;
protected static RequestSpecification server;
protected AbstractFixture() {
setUp();
}
public void setUp() {
if(application == null) {
startApplication();
server = new RequestSpecBuilder()
.setPort(8081)
.setContentType(ContentType.JSON)
.build();
}
}
private void startApplication() {
try {
PathsCollection.Builder rootBuilder = PathsCollection.builder();
Path testClassLocation = PathTestHelper.getTestClassesLocation(getClass());
rootBuilder.add(testClassLocation);
final Path appClassLocation = PathTestHelper.getAppClassLocationForTestLocation(
testClassLocation.toString());
rootBuilder.add(appClassLocation);
application = QuarkusBootstrap.builder()
.setIsolateDeployment(false)
.setMode(QuarkusBootstrap.Mode.TEST)
.setProjectRoot(Paths.get("").normalize().toAbsolutePath())
.setApplicationRoot(rootBuilder.build())
.build()
.bootstrap()
.createAugmentor()
.createInitialRuntimeApplication()
.run();
} catch (BindException e) {
e.printStackTrace();
System.out.println("Address already in use - which is fine!");
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
The code above is working but I can't change the default port 8081 to any other.
If I print the config property in my Test class like below, it prints the port correctly, but quarkus is not running on it:
public class HelloFixture extends AbstractFixture {
public String getGreeting() {
Response response = given(server).when().get("/hello");
System.out.println("Config[port]: " + application.getConfigValue("quarkus.http.port", String.class));
return response.asString();
}
}
How can I specify the configuration file or property programatically before run?
I found the answer. At first, I was referencing the wrong property "quarkus.http.port" instead of "quarkus.http.test-port".
Despite that, I found the way to override properties before run:
...
StartupAction action = QuarkusBootstrap.builder()
.setIsolateDeployment(false)
.setMode(QuarkusBootstrap.Mode.TEST)
.setProjectRoot(Paths.get("").normalize().toAbsolutePath())
.setApplicationRoot(rootBuilder.build())
.build()
.bootstrap()
.createAugmentor()
.createInitialRuntimeApplication();
action.overrideConfig(getConfigOverride());
application = action.run();
...
private Map<String, String> getConfigOverride() {
Map<String, String> config = new HashMap<>();
config.put("quarkus.http.test-port", "18082");
return config;
}

Spring MVC controller create file path

I want to create file path in controller
Already created file path and it's working
try {
Files.write(Paths.get("D:\\app\\app\\java.ini"), data, StandardCharsets.UTF_8, StandardOpenOption.CREATE);
} catch (IOException e) {
e.printStackTrace();
}
Now i want to change this D:\\app\\app\\java.ini and i want to create like resources/java.ini
I don't to give any system full path.
Thanx
The sample code below shows the example that you need:
public class MyClass
{
public static void main(String[] args) {
String test = MyClass.class.getProtectionDomain()
.getCodeSource().getLocation().getPath();
System.out.println(test);
}
}
Assuming that the method you are running is called MyClass, you can have this snippet inside your Java method:
try {
String location = MyClass.class.getProtectionDomain()
.getCodeSource().getLocation().getPath() + "resources/java.ini");
Files.write(location, data, StandardCharsets.UTF_8, StandardOpenOption.CREATE);
} catch (IOException e) {
e.printStackTrace();
}

Implementing different destinations in applications on the Tomcat server

Earlier this year I developed an implementation of the SAP JCO CustomDestinationProvider for one of my Spring MVC tomcat applications. In my application, I use this implementation to call a BAPI in my SAP R/3 system to retrieve data.
I am now working on a second Spring MVC tomcat application that I want to have call a BAPI in my SAP R/3 system to retrieve data. It will be a different BAPI that I will be calling, thus it will be different data that I will be retrieving. Since this is a different application calling a different BAPI, I want to use a different SAP system user in my configurations. This new application will be running on the same physical tomcat server as the first application.
My question is should I develop another implementation of the SAP JCO CustomDestinationProvider for this new application or should I somehow reuse the first implementation? If the answer is that I should develop another implementation for this new application, I would expect then that I would develop another implementation for each new Spring MVC tomcat application that I develop that needs to talk to SAP. Is this correct thinking?
If I do a different implementation for this new application of mine, should I be using the same destination name in the code, or should I use a different name?
Below is the code for my first implementation of CustomDestinationDataProvider:
public class CustomDestinationDataProvider {
public class MyDestinationDataProvider implements DestinationDataProvider {
private DestinationDataEventListener eL;
private HashMap<String, Properties> secureDBStorage = new HashMap<String, Properties>();
public Properties getDestinationProperties(String destinationName) {
try {
Properties p = secureDBStorage.get(destinationName);
if(p!=null) {
if(p.isEmpty())
throw new DataProviderException(DataProviderException.Reason.INVALID_CONFIGURATION, "destination configuration is incorrect", null);
return p;
}
return null;
} catch(RuntimeException re) {
throw new DataProviderException(DataProviderException.Reason.INTERNAL_ERROR, re);
}
}
public void setDestinationDataEventListener(DestinationDataEventListener eventListener) {
this.eL = eventListener;
}
public boolean supportsEvents() {
return true;
}
public void changeProperties(String destName, Properties properties) {
synchronized(secureDBStorage) {
if(properties==null) {
if(secureDBStorage.remove(destName)!=null)
eL.deleted(destName);
} else {
secureDBStorage.put(destName, properties);
eL.updated(destName); // create or updated
}
}
}
}
public ArrayList<String> executeSAPCall(Properties connectProperties, ArrayList<String> partnumbers) throws Exception {
String destName = "ABAP_AS";
SAPDAO sapDAO = new SAPDAO();
ArrayList<MaterialBean> searchResults = new ArrayList<MaterialBean>();
MyDestinationDataProvider myProvider = new MyDestinationDataProvider();
boolean destinationDataProviderRegistered = com.sap.conn.jco.ext.Environment.isDestinationDataProviderRegistered();
JCoDestination dest;
try {
if (!destinationDataProviderRegistered) {
com.sap.conn.jco.ext.Environment.registerDestinationDataProvider(myProvider);
myProvider.changeProperties(destName, connectProperties);
}
} catch(IllegalStateException providerAlreadyRegisteredException) {
logger.error("executeSAPCall: providerAlreadyRegisteredException!");
}
try {
dest = JCoDestinationManager.getDestination(destName);
searchResults = sapDAO.searchSAP(dest, partnumbers);
} catch(JCoException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
return searchResults;
}
}
If the answer is that I should not need to implement another CustomDestinationDataProvider for my second application, what other considerations do I need to keep in mind?
You can only register one DestinationDataProvider so the one you set must be able to handle both (or more) different connections. In order to do this, you need unique names for each connection, i.e. destName can't be the fixed value ABAP_AS, you need to create one for each connection.
Your current implementation of the provider looks good for me, but your method when calling the RFC is mixing the creation of the connection and the actual RFC-calling too much in my eyes. IMHO you should separate the former into its own method, so you can call it from other parts of your application to e.g. do other things than RFC-calling.
I've figured it out! I discovered two different ways to implement CustomDestinationDataProvider so that I could use multiple destinations.
Something that I did that helped out with both of my different solutions was change out the method in CustomDestinationDataProvider that instantiates the MyDestinationDataProvider inner class so that instead of returning ArrayList, it returns JCoDestination. I changed the name of this method from executeSAPCall to getDestination.
The first way that I discovered that allowed me to use multiple destinations, successfully changing out destinations, was to introduce a class variable for MyDestinationDataProvider so that I could keep my instantiated version. Please note that for this solution, the CustomDestinationDataProvider class is still embedded within my java application code.
I found that this solution only worked for one application. I was not able to use this mechanism in multiple applications on the same tomcat server, but at least I was finally able to successfully switch destinations. Here is the code for CustomDestinationDataProvider.java for this first solution:
public class CustomDestinationDataProvider {
private MyDestinationDataProvider gProvider; // class version of MyDestinationDataProvider
public class MyDestinationDataProvider implements DestinationDataProvider {
private DestinationDataEventListener eL;
private HashMap<String, Properties> secureDBStorage = new HashMap<String, Properties>();
public Properties getDestinationProperties(String destinationName) {
try {
Properties p = secureDBStorage.get(destinationName);
if(p!=null) {
if(p.isEmpty())
throw new DataProviderException(DataProviderException.Reason.INVALID_CONFIGURATION, "destination configuration is incorrect", null);
return p;
}
return null;
} catch(RuntimeException re) {
System.out.println("getDestinationProperties: Exception detected!!! message = " + re.getMessage());
throw new DataProviderException(DataProviderException.Reason.INTERNAL_ERROR, re);
}
}
public void setDestinationDataEventListener(DestinationDataEventListener eventListener) {
this.eL = eventListener;
}
public boolean supportsEvents() {
return true;
}
public void changeProperties(String destName, Properties properties) {
synchronized(secureDBStorage) {
if(properties==null) {
if(secureDBStorage.remove(destName)!=null) {
eL.deleted(destName);
}
} else {
secureDBStorage.put(destName, properties);
eL.updated(destName); // create or updated
}
}
}
}
public JCoDestination getDestination(String destName, Properties connectProperties) {
MyDestinationDataProvider myProvider = new MyDestinationDataProvider();
boolean destinationDataProviderRegistered = com.sap.conn.jco.ext.Environment.isDestinationDataProviderRegistered();
if (!destinationDataProviderRegistered) {
try {
com.sap.conn.jco.ext.Environment.registerDestinationDataProvider(myProvider);
gProvider = myProvider; // save our destination data provider in the class var
} catch(IllegalStateException providerAlreadyRegisteredException) {
throw new Error(providerAlreadyRegisteredException);
}
} else {
myProvider = gProvider; // get the destination data provider from the class var.
}
myProvider.changeProperties(destName, connectProperties);
JCoDestination dest = null;
try {
dest = JCoDestinationManager.getDestination(destName);
} catch(JCoException e) {
e.printStackTrace();
} catch (Exception e) {
// TODO Auto-generated catch block
}
return dest;
}
}
This is the code in my servlet class that I use to instantiate and call CustomDestinationDataProvider within my application code:
CustomDestinationDataProvider cddp = new CustomDestinationDataProvider();
SAPDAO sapDAO = new SAPDAO();
Properties p1 = getProperties("SAPSystem01");
Properties p2 = getProperties("SAPSystem02");
try {
JCoDestination dest = cddp.getDestination("SAP_R3_USERID_01", p1); // establish the first destination
sapDAO.searchEmployees(dest, searchCriteria); // call the first BAPI
dest = cddp.getDestination("SAP_R3_USERID_02", p2); // establish the second destination
sapDAO.searchAvailability(dest); // call the second BAPI
} catch (Exception e) {
e.printStackTrace();
}
Again, this solution only works within one application. If you implement this code directly into more than one application, the first app that calls this code gets the resource and the other one will error out.
The second solution that I came up with allows multiple java applications to use the CustomDestinationDataProvider class at the same time. I broke the CustomDestinationDataProvider class out of my application code and created a separate java spring application for it (not a web application) for the purpose of creating a jar. I then transformed the MyDestinationDataProvider inner class into a singleton. Here's the code for the singleton version of CustomDestinationDataProvider:
public class CustomDestinationDataProvider {
public static class MyDestinationDataProvider implements DestinationDataProvider {
////////////////////////////////////////////////////////////////////
// The following lines convert MyDestinationDataProvider into a singleton. Notice
// that the MyDestinationDataProvider class has now been declared as static.
private static MyDestinationDataProvider myDestinationDataProvider = null;
private MyDestinationDataProvider() {
}
public static MyDestinationDataProvider getInstance() {
if (myDestinationDataProvider == null) {
myDestinationDataProvider = new MyDestinationDataProvider();
}
return myDestinationDataProvider;
}
////////////////////////////////////////////////////////////////////
private DestinationDataEventListener eL;
private HashMap<String, Properties> secureDBStorage = new HashMap<String, Properties>();
public Properties getDestinationProperties(String destinationName) {
try {
Properties p = secureDBStorage.get(destinationName);
if(p!=null) {
if(p.isEmpty())
throw new DataProviderException(DataProviderException.Reason.INVALID_CONFIGURATION, "destination configuration is incorrect", null);
return p;
}
return null;
} catch(RuntimeException re) {
throw new DataProviderException(DataProviderException.Reason.INTERNAL_ERROR, re);
}
}
public void setDestinationDataEventListener(DestinationDataEventListener eventListener) {
this.eL = eventListener;
}
public boolean supportsEvents() {
return true;
}
public void changeProperties(String destName, Properties properties) {
synchronized(secureDBStorage) {
if(properties==null) {
if(secureDBStorage.remove(destName)!=null) {
eL.deleted(destName);
}
} else {
secureDBStorage.put(destName, properties);
eL.updated(destName); // create or updated
}
}
}
}
public JCoDestination getDestination(String destName, Properties connectProperties) throws Exception {
MyDestinationDataProvider myProvider = MyDestinationDataProvider.getInstance();
boolean destinationDataProviderRegistered = com.sap.conn.jco.ext.Environment.isDestinationDataProviderRegistered();
if (!destinationDataProviderRegistered) {
try {
com.sap.conn.jco.ext.Environment.registerDestinationDataProvider(myProvider);
} catch(IllegalStateException providerAlreadyRegisteredException) {
throw new Error(providerAlreadyRegisteredException);
}
}
myProvider.changeProperties(destName, connectProperties);
JCoDestination dest = null;
try {
dest = JCoDestinationManager.getDestination(destName);
} catch(JCoException ex) {
ex.printStackTrace();
throw ex;
} catch (Exception ex) {
ex.printStackTrace();
throw ex;
}
return dest;
}
}
After putting this code into the jar file application and creating the jar file (I call it JCOConnector.jar), I put the jar file on the shared library classpath of my tomcat server and restarted the tomcat server. In my case, this was /opt/tomcat/shared/lib. Check your /opt/tomcat/conf/catalina.properties file for the shared.loader line for the location of your shared library classpath. Mine looks like this:
shared.loader=\
${catalina.home}/shared/lib\*.jar,${catalina.home}/shared/lib
I also put a copy of this jar file in the "C:\Users\userid\Documents\jars" folder on my workstation so that the test application code could see the code in the jar and compile. I then referenced this copy of the jar file in my pom.xml file in both of my test applications:
<dependency>
<groupId>com.mycompany</groupId>
<artifactId>jcoconnector</artifactId>
<version>1.0</version>
<scope>system</scope>
<systemPath>C:\Users\userid\Documents\jars\JCOConnector.jar</systemPath>
</dependency>
After adding this to the pom.xml file, I right clicked on each project, selected Maven -> Update Project..., and I then right clicked again on each project and selected 'Refresh'. Something very important that I learned was to not add a copy of JCOConnector.jar directly to either of my test projects. The reason for this is because I want the code from the jar file in /opt/tomcat/shared/lib/JCOConnector.jar to be used. I then built and deployed each of my test apps to the tomcat server.
The code that calls my JCOConnector.jar shared library in my first test application looks like this:
CustomDestinationDataProvider cddp = new CustomDestinationDataProvider();
JCoDestination dest = null;
SAPDAO sapDAO = new SAPDAO();
Properties p1 = getProperties("SAPSystem01");
try {
dest = cddp.getDestination("SAP_R3_USERID_01", p1);
sapDAO.searchEmployees(dest);
} catch (Exception ex) {
ex.printStackTrace();
}
The code in my second test application that calls my JCOConnector.jar shared library looks like this:
CustomDestinationDataProvider cddp = new CustomDestinationDataProvider();
JCoDestination dest = null;
SAPDAO sapDAO = new SAPDAO();
Properties p2 = getProperties("SAPSystem02");
try {
dest = cddp.getDestination("SAP_R3_USERID_02", p2);
sapDAO.searchAvailability(dest);
} catch (Exception ex) {
ex.printStackTrace();
}
I know that I've left out a lot of the steps involved in first getting the SAP JCO 3 library installed on your workstation and server. I do hope that this helps out at least one other person of getting over the hill of trying to get multiple spring mvc java spplications talking to SAP on the same server.

htmlunit javascript performance

I made a performance test of htmlunit against selenium with firefoxdriver and firefox 21.
The performance test was made on my windows7 machine through Eclipse.
When both have javascript disabled, the performance is the same. When both have javascript turned on htmlunit 2.12 is 150% slower than firefox.
I imagine that this is due the superiority of the spidermonkey engine on rhino.
Is there a way to configure rhino that it will be faster?
Is there anpther way we can speed htmlunit up?
package utils;
import java.io.IOException;
import java.net.MalformedURLException;
import java.text.DateFormat;
import java.util.Date;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.firefox.FirefoxDriver;
import org.openqa.selenium.firefox.FirefoxProfile;
import com.gargoylesoftware.htmlunit.BrowserVersion;
import com.gargoylesoftware.htmlunit.FailingHttpStatusCodeException;
import com.gargoylesoftware.htmlunit.WebClient;
import com.gargoylesoftware.htmlunit.html.HtmlPage;
public class PerformanceTest {
public static void main(String[] args) {
String[] urls = new String[] {
...
};
Date beforeSelenium = new Date();
System.out.println("Going to run selenium");
testSelenium(urls);
Date afterSelenium = new Date();
Date beforehtmlUnit= new Date();
System.out.println("Going to run htmlunit");
testHtmlUnit(urls);
Date afterhtmlUnit = new Date();
System.out.println(
DateFormat.getTimeInstance(DateFormat.LONG).format(beforeSelenium));
System.out.println(
DateFormat.getTimeInstance(DateFormat.LONG).format(afterSelenium));
System.out.println(
DateFormat.getTimeInstance(DateFormat.LONG).format(beforehtmlUnit));
System.out.println(
DateFormat.getTimeInstance(DateFormat.LONG).format(afterhtmlUnit));
}
public static void testSelenium(String[] urls) {
WebDriver driver = new FirefoxDriver();
int i=0;
for(String url:urls) {
i++;
System.out.println(i);
// And now use this to visit Google
driver.get(url);
String str = driver.getPageSource();
System.out.println(str);
}
driver.close();
}
public static void testHtmlUnit(String[] urls) {
WebClient client = new WebClient(BrowserVersion.FIREFOX_17);
client.getOptions().setJavaScriptEnabled(true);
client.getOptions().setRedirectEnabled(true);
client.getOptions().setThrowExceptionOnScriptError(false);
client.getOptions().setCssEnabled(true);
client.getOptions().setUseInsecureSSL(true);
client.getOptions().setThrowExceptionOnFailingStatusCode(false);
int i=0;
for(String url:urls) {
i++;
System.out.println(i);
// And now use this to visit Google
HtmlPage page;
try {
page = client.getPage(url);
String str = page.asText();
System.out.println(str);
} catch (FailingHttpStatusCodeException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
HtmlUnit use a modified, repacked Rhino JavaScript engine. By default is used a interpreter mode. You can enable JavaScript optimization. Then the JavaScript will be compiled to Java byte code.
WebClient webClient = new WebClient();
JavaScriptEngine sriptEngine = webClient.getJavaScriptEngine();
HtmlUnitContextFactory factory = sriptEngine.getContextFactory();
Context context = factory.enterContext();
context.setOptimizationLevel(9);
But this must not speed up your page. It can also slow down it.
The JS engine is the major problem on HtmlUnit performance.
There are some options:
Change Rhino Optimization Settings
Write Rhino Optimized Javascript (hardly it will be enough).
Adapt an external engine (like Chromium).
Wait for Nashorn.
Switch to PhantomJs.

HTMLUnit webClient.getPage(locationToPing) is blocked when the jar is invoked from Runtime.exec()

I am writing an application that needs to load a jar periodically. The Jar fetches the content of a website making use of HTMLUnit.When this jar is run from commond prompt it runs as expected. But when I run it using java code by making use of Runtime, it blocks at the place , page= webClient.getPage(locationToPing);
and doesnt proceed furhter.
The Jar contains only one java class as given below,
package tempproj2;
import com.gargoylesoftware.htmlunit.BrowserVersion;
import com.gargoylesoftware.htmlunit.WebClient;
import com.gargoylesoftware.htmlunit.html.HtmlPage;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
public class Fetcher {
String locationToPing;
volatile WebClient webClient = new WebClient(BrowserVersion.FIREFOX_3_6);
HtmlPage page ;
public static final long SLEEP_TIME_IF_CONNECTION_WAS_REFUSED=10000; //SECS
public long connectionRefusedTime=0;
private static Fetcher theOnlyInstanceOfThisClass=new Fetcher();
public static Fetcher getInstance(){
return theOnlyInstanceOfThisClass;
}
private Fetcher(){
init();
fetchUsingGet();
}
private void init(){
locationToPing="http://www.mail.yahoo.com";
}
private void fetchUsingGet(){
try {
System.out.println("-----------Start 1 --------------") ;
webClient.setUseInsecureSSL(true);
webClient.setThrowExceptionOnScriptError(false);
System.out.println("-----------Start 2 --------------") ;
webClient.setJavaScriptEnabled(true);
System.out.println("-----------Start 3 --------------") ;
webClient.setTimeout(5000); //30 secs - its int n not long be careful abt it.
System.out.println("-----------Start 4 --------------locationToPing="+locationToPing) ;
page= webClient.getPage(locationToPing);
System.out.println("-----------Start 5 --------------"+page.asXml()) ;
} catch (Exception ex) {
System.out.println("-----------IC Fetecher Error here --------------"+ex.getMessage()) ;
connectionRefusedTime=System.currentTimeMillis();
ex.printStackTrace();
}
}
private void reload(){
if(page==null){
fetchUsingGet();
return;
}
try {
page=(HtmlPage)page.refresh();
} catch (java.net.SocketTimeoutException ex) {
fetchUsingGet();
ex.printStackTrace();
}catch(IOException ex){
ex.printStackTrace();
}
}
public static void main(String ar[]){
Fetcher fetcher=new Fetcher();
while(true){
try {
Thread.sleep(4*1000);
} catch (InterruptedException ex) {
Logger.getLogger(Fetcher.class.getName()).log(Level.SEVERE, null, ex);
}
fetcher.reload();
}
}
}
Given below are the different ways I tried to run the above code
Run the class as it is - Runs fine.
Make a Jar of the above class and run from the command prompt using java -jar , command - Runs fine.
Make a Jar of above class and run it from another java class using the following code,
try {
String execCmd="java -jar "+downloadApplicationJarLocation.getAbsolutePath();
Process pr=Runtime.getRuntime().exec(execCmd) ;
InputStreamReader is = new InputStreamReader(pr.getInputStream());
BufferedReader br = new BufferedReader(is);
String line = null;
String processMessage="";
while ((line = br.readLine()) != null) {
System.err.println("Line 1 "+line) ;
processMessage+=line;
}
System.out.println("Finished ");
is.close();
br.close();
} catch (IOException ex) {
ex.printStackTrace();
}
But when I try the above code only the code up to page= webClient.getPage(locationToPing); is executed and gets blocked. "Start 5" is never printed on the screen.
I modifed the above code and instead of directly calling the e Java -jar command in the Runtime.exec(), I placed it in a batch file and called this batch file.
Process pr=Runtime.getRuntime().exec(batchFileLocation) ;
Now it executed as expected and didnt block the code.Also "Start 5" gets printed on the screen.
My application needs to invoke the jar periodically from java and destroy the previous process if any. So Option 4 doesnt hold good for me as the subprocess is stil alive and not very easy to destroy the subprocess.
Option 3 is the ideal way for me but am quite not able to understand why does it get blocked and doesnt proceed any longer? Is it something to do with threading? Am I using HTMLUnit the way how it is supposed to be used?
Thanks in Advance

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