I have the same problem as described in the question Call getPage from htmlunit WebClient with JavaScript disabled and setTimeout set to 10000 waits forever.
There is only one relevant (complicated) possible answer there (by theytoo). So I was wondering if:
Does someone have a simpler answer?
Can someone verify the solution works?
Code I used:
package main;
import java.io.IOException;
import java.net.MalformedURLException;
import com.gargoylesoftware.htmlunit.FailingHttpStatusCodeException;
import com.gargoylesoftware.htmlunit.WebClient;
public class Test {
public static void main(final String[] args) {
final WebClient webClient = new WebClient();
webClient.setTimeout(1000);
try {
System.out.println("Querying");
webClient.getPage("http://www.google.com");
System.out.println("Success");
} catch (final FailingHttpStatusCodeException e) {
System.out.println("One");
e.printStackTrace();
} catch (final MalformedURLException e) {
System.out.println("Two");
e.printStackTrace();
} catch (final IOException e) {
System.out.println("Three");
e.printStackTrace();
} catch (final Exception e) {
System.out.println("Four");
e.printStackTrace();
}
System.out.println("Finished");
}
}
Output (removed all CSS and JS warnings):
Querying
Success
Finished
After changing timeout from 1000 to 1 (I won't hit google in less than 1 ms):
Querying
Three
org.apache.http.conn.ConnectTimeoutException: Connect to www.google.com:80 timed out
at com.gargoylesoftware.htmlunit.SocksSocketFactory.connectSocket(SocksSocketFactory.java:92)
at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:148)
at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:149)
at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:121)
at org.apache.http.impl.client.DefaultRequestDirector.tryConnect(DefaultRequestDirector.java:573)
at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:425)
at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:820)
at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:776)
at com.gargoylesoftware.htmlunit.HttpWebConnection.getResponse(HttpWebConnection.java:152)
at com.gargoylesoftware.htmlunit.WebClient.loadWebResponseFromWebConnection(WebClient.java:1439)
at com.gargoylesoftware.htmlunit.WebClient.loadWebResponse(WebClient.java:1358)
at com.gargoylesoftware.htmlunit.WebClient.getPage(WebClient.java:307)
at com.gargoylesoftware.htmlunit.WebClient.getPage(WebClient.java:373)
at com.gargoylesoftware.htmlunit.WebClient.getPage(WebClient.java:358)
at main.Test.main(Test.java:17)
Finished
Conclusion: I can't reproduce it and it works as expected
Related
I am unable to catch the STException thrown by the STGroupFile. This is a problem. I need to abort if the template is bad. To reproduce this problem, I have this incorrect template file called tmp.stg:
temp1(param1)::=<<
%if(param1)%
%param1:{%temp2(p)%}; separator"\n"%
%endif%
>>
And this groovy code to process it:
#!/usr/bin/env groovy
#Grab(group="org.antlr", module="ST4", version="4.0.8")
import org.stringtemplate.v4.STGroupFile;
import org.stringtemplate.v4.NumberRenderer;
public class Gex {
public static void main(String [] args) {
System.out.println("Processing...")
File fn = new File("tmp.stg")
STGroupFile group;
try {
group = new STGroupFile(fn.toString());
} catch (Throwable e) {
throw new Exception("Caught first exception");
}
try {
group.registerRenderer(Integer.class, new NumberRenderer());
} catch (Throwable e) {
throw new Exception("Caught second exception");
}
throw new Exception("You should not see this");
}
}
Gex.main()
When I run that script, I get an error message but I cannot catch the exception:
can't load group file file:tmp.stg
The error message comes from STGroupFile.java:
throw new STException("can't load group file "+fileName, e);
But I am unable to catch this exception. How can I catch this exception and abort?
Following the advice of The ANTLR Guy, I extended the STErrorListener to throw an exception instead of printing a message to stderr. It looks like this:
File: lib/GexListener.groovy
import org.stringtemplate.v4.STErrorListener;
import org.stringtemplate.v4.misc.STMessage;
import org.stringtemplate.v4.misc.ErrorType;
class GexListener implements STErrorListener {
#Override
public void compileTimeError(STMessage msg) {
throw new Exception(msg.toString());
}
#Override
public void runTimeError(STMessage msg) {
if ( msg.error != ErrorType.NO_SUCH_PROPERTY ) { // ignore these
throw new Exception(msg.toString());
}
}
#Override
public void IOError(STMessage msg) {
throw new Exception(msg.toString());
}
#Override
public void internalError(STMessage msg) {
throw new Exception(msg.toString());
}
public void error(String s) { error(s, null); }
public void error(String s, Throwable e) {
System.err.println(s);
if ( e!=null ) {
throw new Exception(msg.toString());
}
}
}
Then the master script bin/gex.groovy looks like this:
#!/bin/bash
//usr/bin/env groovy -cp ${0%/*}/../lib "$0" "$#"; exit $?
#Grab(group="org.antlr", module="ST4", version="4.0.8")
import org.stringtemplate.v4.STGroupFile;
import org.stringtemplate.v4.NumberRenderer;
import GexListener
public class Gex {
public static void main(String [] args) {
System.out.println("Processing...")
File fn = new File("tmp.stg")
STGroupFile group;
GexListener listener = new GexListener();
group = new STGroupFile(fn.toString());
group.setListener(listener);
group.registerRenderer(Integer.class, new NumberRenderer());
System.out.println("You should not see this line")
}
}
Gex.main()
When it executes, there is a nasty side effect where the stacktrace is printed twice, but the program aborts before printing the last sentence "You should not see this line", which is the desired behaviour.
As you pointed out in a separate email: "I discovered that the exception is actually caught and not re-thrown. This happens inside STGroup.java:"
catch (Exception e) {
errMgr.IOError(null, ErrorType.CANT_LOAD_GROUP_FILE, e, fileName);
}
Why not override the IOError function (or a function in the listener that it calls?) to just re-throw e?
I am trying to send the images captured from client to server,images are captured using robot class and writing to client socket. In server i am reading the buffered image and writing into server local storage area.I want client capture the screenshots at a regular interval and send to server.server reads the images and stores in its repository.
public class ServerDemo {
public static void main(String[] args) {
try {
ServerSocket serversocket=new ServerSocket(6666);
System.out.println("server listening..........");
while(true)
{
Thread ts=new Thread( new ServerThread(serversocket.accept()));
ts.start();
System.out.println("server thread started.........");
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
ServerThread.java
public class ServerThread implements Runnable {
Socket s;
BufferedImage img = null;
String savelocation="d:\\Screenshot\\";
public ServerThread(Socket server) {
this.s=server;
}
#Override
public void run() {
try {
System.out.println("trying to read Image");
img = ImageIO.read(s.getInputStream());
System.out.println("Image Reading successful.....");
} catch (IOException e) {
System.out.println(e);
// TODO Auto-generated catch block
e.printStackTrace();
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
File save_path=new File(savelocation);
save_path.mkdirs();
try {
ImageIO.write(img, "JPG",new File(savelocation+"img-"+System.currentTimeMillis()+".jpg"));
System.out.println("Image writing successful......");
} catch (IOException e) {
// TODO Auto-generated catch block
System.out.println(e);
e.printStackTrace();
}
}
}
ClientDemo.java
public class ClientDemo {
public static void main(String[] args) throws InterruptedException {
try {
Socket client=new Socket("localhost", 6666);
while(true)
{
System.out.println("Hello");
Thread th=new Thread(new ClientThread(client));
th.start();
System.out.println("Thread started........");
th.sleep(1000*60);
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
ClientThread.java
public class ClientThread implements Runnable{
Socket c;
public ClientThread(Socket client) {
this.c=client;
}
#Override
public void run() {
try {
System.out.println("client");
//while(true){
Dimension size=Toolkit.getDefaultToolkit().getScreenSize();
Robot robot=new Robot();
BufferedImage img=robot.createScreenCapture(new Rectangle(size));
System.out.println("Going to capture client screen");
ImageIO.write(img, "JPG", c.getOutputStream());
System.out.println("Image capture from client success...!");
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (AWTException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
Server Console
server listening..........
server thread started.........
trying to read Image
Image Reading successful.....
Image writing successful......
Client console
Hello
Thread started........
client
Going to capture client screen
Image capture from client success...!
Hello
Thread started........
client
Going to capture client screen
Hello
Thread started........
client
Going to capture client screen
Repeat like this.This code works perfectly for first time after that it fails.Each time runs it capture the images only once.What change i have to make to capture and write the images at regular intervals...Please help me
Try this in ClientDemo.java
while(true)
{
System.out.println("Hello");
Socket client=new Socket("localhost", 6666);
Thread th=new Thread(new ClientThread(client));
th.start();
System.out.println("Thread started........");
th.sleep(1000*60);
}
And make sure that you close the client socket once the thread(ClientThread.java) is completed may be in finally block or at the end of code.
You don't need ImageIO for the server end of this. Just send and receive bytes:
while ((count = in.read(buffer()) > 0)
{
out.write(buffer, 0, count);
}
I see the problem is in the server. The first time it accepts a connection from the client,Thread ts=new Thread( new ServerThread(serversocket.accept())); but the client only connects once Socket client=new Socket("localhost", 6666); When the first transfer is completed the server stay again in the accept waiting for the client to make the connect which never happen again. Therefore either you should issue only one accept and use that socket for every transfer or close both sockets, at the client and server, and make the accept/connect again.
For a Java class I am taking, I need to use sockets to pass data back and forth between client and server. While I can get examples to work passing string data, I need to be able to pass custom class objects (i.e. a product) and lists of these objects back and forth. I cannot get the server piece to successfully read the input. I tried to create a simple example of my code to see if anyone can pinpoint the issue. I do understand that I don't have the code complete, but I cannot even get the server to read the object the the class is writing to the stream (in this case, I am writing a string just in an attempt to get it to work, but need to read/write objects). Here is my code. I have spent hours and hours trying this and researching other people's questions and answere, but still can't get this to work.
Here the sample code:
simple server:
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.ServerSocket;
import java.net.Socket;
public class simpleServer {
public static final int PORT_NO = 8888;
static ObjectInputStream serverReader = null;
public static void main(String[] args) throws IOException, InterruptedException {
ServerSocket serverSocket = new ServerSocket(PORT_NO);
System.out.println("... server is accepting request");
Object myObject = null;
while (true) {
Socket socket = serverSocket.accept();
System.out.println("creating reader");
ObjectOutputStream objOut = new ObjectOutputStream(socket.getOutputStream());
serverReader = new ObjectInputStream(socket.getInputStream());
System.out.println("created reader");
try {
System.out.println("try to read");
myObject = serverReader.readObject();
System.out.println("read it");
System.out.println(myObject);
if (myObject != null) objOut.writeUTF("Got something");
else objOut.writeUTF("got nothing");
if ("quit".equals(myObject.toString())) serverSocket.close();
} catch (ClassNotFoundException e1) {
// TODO Auto-generated catch block
System.out.println("cath for readobject");
}
catch (Exception e) {
System.out.println("other error");
System.out.println(e.getMessage());
}
}
}
}
simple client:
public static void main(String[] args) {
Socket socket;
try {
socket = new Socket("localhost", ProductDBServer.PORT_NO);
ObjectOutputStream objOut = new ObjectOutputStream(socket.getOutputStream());
ObjectInputStream objIn = new ObjectInputStream(socket.getInputStream());
objOut.writeUTF("loadProductsFromDisk");
objOut.flush();
String myString = objIn.toString();
//System.out.println(myString);
if (!"quit".equals(objIn.toString().trim())) {
//System.out.println("reading line 1");
String line;
try {
line = (String)objIn.readObject();
//System.out.println("line is " + line);
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
objIn.close();
//System.out.println("result: " + line);
}
System.out.println("closing socket");
socket.close();
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
System.out.println("Unknownhostexception");
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
System.out.println("ioexception");
e.printStackTrace();
}
}
The code appears to run to the point on the server side where it trys to read the object I sent, and then dies. Can someone see what I am doing wrong? This seems to be such a simple thing to do, and yet I can't seem to get it to work. Thanks for any help!
To write objects to an ObjectOutputStream you need to call writeObject().
Not writeUTF().
To read objects from an ObjectInputStream you need to call readObject().
Not toString().
See in your code:
// Simple Client
objOut.writeUTF("loadProductsFromDisk"); // Line 8
You are sending the String "loadProductsFromDisk" in the UTF-8 format towards the server side.
So in order to receive it and read it over the server side, you will need something like this:
String clientReq = serverReader.readUTF();
Where, serverReader is your ObjectInputStream object.
Otherwise, if you wish to send and receive objects you must use the
writeObject() & readObject() methods respectively.
I've managed to run the code in this question here properly in a test java project with no problem, but when I am following the exact same procedure to import HtmlUnit in my webserver, i keep getting the org.apache.http.protocol.BasicHttpContext: method <init>()V not found error.
the code im trying to run:
package com.testing;
import java.io.IOException;
import java.net.MalformedURLException;
import com.gargoylesoftware.htmlunit.FailingHttpStatusCodeException;
import com.gargoylesoftware.htmlunit.WebClient;
public class testingUnit {
public static void main(final String[] args) {
final WebClient webClient = new WebClient();
webClient.setTimeout(1000);
try {
System.out.println("Querying");
webClient.getPage("https://bulksms.vsms.net/register/");
System.out.println("Success");
} catch (final FailingHttpStatusCodeException e) {
System.out.println("One");
e.printStackTrace();
} catch (final MalformedURLException e) {
System.out.println("Two");
e.printStackTrace();
} catch (final IOException e) {
System.out.println("Three");
e.printStackTrace();
} catch (final Exception e) {
System.out.println("Four");
e.printStackTrace();
}
System.out.println("Finished");
}
}
Console:
Querying
Exception in thread "main" java.lang.NoSuchMethodError: org.apache.http.protocol.BasicHttpContext: method <init>()V not found
at org.apache.http.impl.client.AbstractHttpClient.createHttpContext(AbstractHttpClient.java:273)
at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:797)
at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:776)
at com.gargoylesoftware.htmlunit.HttpWebConnection.getResponse(HttpWebConnection.java:152)
at com.gargoylesoftware.htmlunit.WebClient.loadWebResponseFromWebConnection(WebClient.java:1439)
at com.gargoylesoftware.htmlunit.WebClient.loadWebResponse(WebClient.java:1358)
at com.gargoylesoftware.htmlunit.WebClient.getPage(WebClient.java:307)
at com.gargoylesoftware.htmlunit.WebClient.getPage(WebClient.java:373)
at com.gargoylesoftware.htmlunit.WebClient.getPage(WebClient.java:358)
at com.testing.testingUnit.main(testingUnit.java:16)
Figured it out after posting the screenshot here. I had totally forgot to update the web app libraries. I did that and deleted all the outdated versions of jars I had (in the webcontent/lib folder), and the code above worked like a charm. Cheers!
I'm experimenting on ServerSocket in Java on Windows 7 x64.
I wrote a little program that host a HTTP server on port 8080 and only returns a static HTML response that contains the toString() of the class loader.
What I did in the program mainly:
Create a ServerSocket
call setReuseAddress(false) on the serverSocket
Bind port 8080 to this socket
Use a forever loop to accept socket and give response
First I tried with JRE 1.6.0_23 and everything is great: first instance launched and responds normally, second instance cannot be launched since exception is thrown:
Exception in thread "main" java.net.BindException: Address already in use: JVM_Bind
Unexpected thing happens when I tried with JRE 1.7.0_5: both instance can be launched successfully but only the first instance gives responses. After the first instance is kill, the second instance then starts to responds.
Am I doing anything wrong or is this a bug of JRE 7?
import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.ServerSocket;
import java.net.Socket;
public class TestServerSocket {
private static final String HEADER = "HTTP/1.1 200 OK\r\n" + "Content-type: text/html\r\n"
+ "Connection: close\r\n" + "\r\n";
private static final int PORT = 8080;
private static void handle(Socket socket) {
System.out.println(socket.getInetAddress() + ":" + socket.getPort());
StringBuilder buffer = new StringBuilder();
buffer.append(HEADER);
buffer.append(TestServerSocket.class.getClassLoader());
try {
socket.getOutputStream().write(buffer.toString().getBytes());
} catch (IOException e) {
} finally {
try {
socket.close();
} catch (IOException e) {
}
}
}
public static void main(String[] args) throws IOException {
int port;
try {
port = Integer.parseInt(args[0]);
} catch (Exception e) {
port = PORT;
}
final ServerSocket server = new ServerSocket();
server.setReuseAddress(false);
server.bind(new InetSocketAddress(port));
// Terminator thread, stop when Ctrl-D is entered
new Thread() {
public void run() {
try {
while (System.in.read() != 4);
} catch (IOException e) {
e.printStackTrace();
}
try {
server.close();
} catch (IOException e) {
}
System.exit(0);
}
}.start();
System.out.println("Listening on: " + port);
Socket client = null;
while (true) {
try {
client = server.accept();
handle(client);
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
To Isolate the problem, I would recommend that you run the following test code.
Apache HttpCore basic server. It's standard API and uses ServerSocket in this particular example, so there is a very small chance that it would fail on your environment ( java 7).
In case it fails you will know for sure problem is not with your code. Meanwhile I will try your code on JDK 7 on my work-machine and will update.