How to get proxy settings from system settings in Java - java

I'm looking form way how to get system proxy information in Java under Windows, but I've found just one way. But it does not work for me.
public static void main(String[] args) throws Throwable {
System.setProperty("java.net.useSystemProxies", "true");
System.out.println("detecting proxies");
List<Proxy> pl = ProxySelector.getDefault().select(new URI("http://ihned.cz/"));
for (Proxy p : pl)
System.out.println(p);
Proxy p = null;
if (pl.size() > 0) //uses first one
p = pl.get(0);
System.out.println(p.address());
System.out.println("Done");
}
When I run the program, I get:
detecting proxies
DIRECT
null
Done
Java means, that I'm situated directly on internet. But it's wrong. I'm behind proxy. I'm unable to get the solution for my computer.

As we discussed in the comments the proxy settings is just applied for some of browsers you use.
If you want Java to use the same settings you need to manually put it into the java network settings (check this web page for details).

Thanks to Dacwe. The problem is, that browser does not use any system proxy, but it sets proxy self using a script. Thus there are not any proxies in the system and Java cannot reach them.

Related

Why does Apache Commons VFS consider Http Proxy and Socks5 Proxy but simply ignore Socks4 Proxy?

I am working on a application that connects to an SFTP server and downloads files using Apache Commons VFS, it works just fine, with the exception that the system needs to allow the user to specify a proxy, as needed.
Now, I know Apache Commons VFS is built on top of Jsch and I know Jsch contains the classes: com.jcraft.jsch.ProxyHTTP, com.jcraft.jsch.ProxySOCKS4 and com.jcraft.jsch.ProxySOCKS5.
The code below is an extract of VFS class org.apache.commons.vfs2.provider.sftp.SftpClientFactory:
public static Session createConnection(
...
final SftpFileSystemConfigBuilder.ProxyType proxyType = builder.getProxyType(fileSystemOptions);
...
final String proxyUser = builder.getProxyUser(fileSystemOptions);
final String proxyPassword = builder.getProxyPassword(fileSystemOptions);
Proxy proxy = null;
if (SftpFileSystemConfigBuilder.PROXY_HTTP.equals(proxyType)) {
proxy = createProxyHTTP(proxyHost, proxyPort);
((ProxyHTTP)proxy).setUserPasswd(proxyUser, proxyPassword);
} else if (SftpFileSystemConfigBuilder.PROXY_SOCKS5.equals(proxyType)) {
proxy = createProxySOCKS5(proxyHost, proxyPort);
((ProxySOCKS5)proxy).setUserPasswd(proxyUser, proxyPassword);
} else if (SftpFileSystemConfigBuilder.PROXY_STREAM.equals(proxyType)) {
proxy = createStreamProxy(proxyHost, proxyPort, fileSystemOptions, builder);
}
...
As you can you see, there's no "if" statement to instantiate ProxySOCKS4!
I have duplicated the SftpClientFactory class, set my version to load before the original class on the classpath and changed the code as follow:
public static Session createConnection(
...
final SftpFileSystemConfigBuilder.ProxyType proxyType = builder.getProxyType(fileSystemOptions);
...
final String proxyUser = builder.getProxyUser(fileSystemOptions);
final String proxyPassword = builder.getProxyPassword(fileSystemOptions);
Proxy proxy = null;
if (SftpFileSystemConfigBuilder.PROXY_HTTP.equals(proxyType)) {
proxy = createProxyHTTP(proxyHost, proxyPort);
((ProxyHTTP)proxy).setUserPasswd(proxyUser, proxyPassword);
/// change start (I also created the PROXY_SOCKS4 constant)
} else if (SftpFileSystemConfigBuilder.PROXY_SOCKS4.equals(proxyType)) {
proxy = createProxySOCKS4(proxyHost, proxyPort);
((ProxySOCKS4)proxy).setUserPasswd(proxyUser, proxyPassword);
/// change end
} else if (SftpFileSystemConfigBuilder.PROXY_SOCKS5.equals(proxyType)) {
proxy = createProxySOCKS5(proxyHost, proxyPort);
((ProxySOCKS5)proxy).setUserPasswd(proxyUser, proxyPassword);
} else if (SftpFileSystemConfigBuilder.PROXY_STREAM.equals(proxyType)) {
proxy = createStreamProxy(proxyHost, proxyPort, fileSystemOptions, builder);
}
...
.. and guess what, when I set my application to use a Socks 4 Proxy it works alright with the change above. It is important to say that setting the application to work with Socks 5 does not work if the proxy server is a Socks 4 type, and that's true not only for my application with VFS, but also any other client I tested, like Fillezila or WinSCP.
So, the main question is:
Why does VFS predicts the usage of ProxyHTTP, ProxySOCKS5 but completely ignores the JSch ProxySOCKS4 class? Am I missing some SFTP or Proxy concept here or should I consider VFS bugged? That's the first time I work with VFS.
Please consider the question in bold as the main question not to make it too broad.
I wasn't able to get or find a better answer in time, so what I did to solve my problem was exactly what I described in the question.
I duplicated the classes SftpClientFactory e SftpFileSystemConfigBuilder, made the necessary adjustments and used them instead of the original classes, it's ugly and now I am stuck with a specific VFS version, I know, but the problem was solved.
Lesson for next time: use Jsch instead of VFS.
I'll leave the question open though, in case someone else have a proper solution or answer.

Using external server restlet framework

I am using the Restlet Framework, but now I want to change to a proper server instead of using localhost.
I have already added my php files (they access the java files using the rest_server URL) to the server's folder and my java files as well, but I am not sure how to change the code so it identifies where the new location of the files is.
Here is the code from IdentiscopeServer (constructor empty):
public static void main(String[] args) throws Exception {
//setsup our security manager
if (System.getSecurityManager() == null){
System.setSecurityManager(new SecurityManager());
}
identiscopeServerApp = new IdentiscopeServerApplication();
IdentiscopeServer server = new IdentiscopeServer();
server.getServers().add(Protocol.HTTP,8888);
server.getDefaultHost().attach("", identiscopeServerApp);
server.start();
}
I guess that the correct line to change is the one with "Protocol.HTTP, 8888". If the address of my new server is http://devweb2013.co.uk/research/Identiscope, how exactly do I set this up? Is there anything else necessary for it to work apart from just moving the files to a folder in the server?
The IdensticopeServerApplication is the following:
public class IdentiscopeServerApplication extends Application {
public IdentiscopeServerApplication() {
}
public Restlet createInboundRoot() {
Router router = new Router(getContext());
//attaches the /tweet path to the TweetRest class
router.attach("/collectionPublic", CollectionPublicREST.class);
router.attach("/collectionPrivate", CollectionPrivateREST.class);
router.attach("/analysis", AnalysisREST.class);
return router;
}
}
Thank you in advance, it is my first time using this Framework.
If I understand you correctly, you just want to run your main() method as the server, correct? In this case, the code for main() needs to be in a location that -- when running -- can provide the service at http://devweb2013.co.uk/research/Identiscope. Since you haven't stated what kind of server you are putting the code, I can't say where the best place to put the code would be. I assume you have superuser privileges on your deployment server, since the URL you provided implies port 80 will be serving your Identiscope web service (port 80 is a privileged port on most OS's). So as an answer, I can only provide general information.
On your deployment server, port 80 must be free (i.e. nothing else should be acting as a web server on port 80 on that machine) and the IdentiscopeApplication must be running on port 80. To do that, you need only change the line:
server.getServers().add(Protocol.HTTP,8888);
to:
server.getServers().add(Protocol.HTTP, 80);
then run the application as a user that is allowed to start servers on port 80 (preferably NOT the superuser). If you haven't already, you will need to get Java running on your deployment server and make sure all Restlet libraries are in the classpath where you plan to run your application.
If I understand what you are trying to do, then this should do the trick.

Open browser with proxy setting set from Java

I need to open a browser from Java code. I understand this can be done as follows :
java.awt.Desktop.getDesktop().browse(java.net.URI.create("http://google.com"));
But i need the browser to use certain proxy settings as well. (i.e. when the browser opens, its proxy settings must be set to certain values.) I tried using the follwoing code but it doesnt work :
public static void main(String asf[]){
System.setProperty("java.net.useSystemProxies", "true");
System.setProperty("http.proxyHost", "127.0.0.1");
System.setProperty("http.proxyPort", "8080");
try {
java.awt.Desktop.getDesktop().browse(java.net.URI.create("http://google.com"));
} catch (IOException e) {
e.printStackTrace();
}
System.out.println("done");
}
Setting the proxy from command line using
java -Dhttp.proxyHost=webcache.example.com -Dhttp.proxyPort=8080
is not an option for me. How do i accomplish this?
Your code is largely correct which deals with setting the proxy, but in case it is not working there is another way to set the proxy via Java code and that is via the proxy class.
SocketAddress addr = new InetSocketAddress("socks.example.com", 1080);
Proxy proxy = new Proxy(Proxy.Type.SOCKS, addr);
Socket socket = new Socket(proxy);
InetSocketAddress dest = new InetSocketAddress("server.example.org", 1234);
socket.connect(dest);
Here the socket will try to connect to its destination address (server.example.org:1234) through the specified SOCKS proxy.
For more detail you can go through the Standard Java Documentation for Proxies
Your solution for opening a browser can be improved by adding a check
if(Desktop.isDesktopSupported())
{
Desktop.getDesktop().browse(new URI("http://www.google.com"));
}
this is in addition to your solution .... maybe you can call it an alternate way
try {
Process p=Runtime.getRuntime().exec("cmd /c start http://www.google.com");
}
catch(IOException e1) {
System.out.println(e1);
}
The Google Chromes proxy switches can be useful here. We can just make a shortcut for the chrome browser whose target contains the switch --proxy-server=127.0.0.1:8080 . Now this shortcut can be opened from java code using the Runtime class' exec method. The arguments to exec will be "cmd /c start /d \"d:\" chrome.lnk" where d: is the path of my shortcut. A detailed description of this technique can be found here http://sleepingthreads.blogspot.in/2013/07/open-browser-with-proxy-settings-set.html
Note that Google states that the use of switches is not recommended. So use this as a temporary solution only.

How to set specify proxy for load server application in JVM & Jboss?

I have a load server application which switches between two applications, App1 & App2. Each App has its own IFrame which talks to a bank, but when the bank returns back data, the load server cannot distinguish which app was that. I investigated on that, then I found out that it is the proxy issue.
As a result, I tried to force the application to use proxyHost & proxyport but it did n't work, then I forced the Jboss to use the specific proxyHost & proxyport but it did n't work either. It use a default proxy on the box and it does n't care about my configuration.
Setting the proxyHost & proxyPort at the Jboss startup script (bin\run.bat):
the Jboss logs showed that it had accepted the java VM arguments (e.g. -Dhttp.proxyHost=XX.XX.XX.XX -Dhttp.proxyPort=8080), when we ran
the application, it would still go through the default proxy settings on the box.
I searched in google & stackoverflow and tried different ideas but didn't work.
Could someone please shed some light on it?
Could you try running your apps with the following JVM args: -Dsun.net.inetaddr.ttl=0 -Dnetworkaddress.cache.ttl=0?
The DNS settings get cached after a successful request, these parameters will disable the caching.
You can force an application to ignore any VM arguments for proxyHost and
just use the default proxy of the box it’s running on. You can write a small java program which just prints the default proxy and ran it on the specific box (like this one):
import java.net.InetSocketAddress;
import java.net.ProxySelector;
import java.net.URISyntaxException;
import java.util.Iterator;
import java.util.List;
import java.net.URI;
public class PrintDefaultProxy {
public static void main(String[] args) {
// If you clear these 2 properties then set java.net.useSystemProxies to true, it
// will use the default System Proxy and ignore any settings given to the VM
// e.g. http.proxyHost & http.proxyPort
System.setProperty("http.proxyHost", "");
System.setProperty("http.proxyPort", "");
System.setProperty("java.net.useSystemProxies", "true");
System.out.println("detecting proxies");
List l = null;
try {
String url = "http://google.com.au/";
l = ProxySelector.getDefault().select(new URI(url));
}
catch (URISyntaxException e) {
e.printStackTrace();
}
if (l != null) {
for (Iterator iter = l.iterator(); iter.hasNext();) {
java.net.Proxy proxy = (java.net.Proxy) iter.next();
System.out.println("proxy Type : " + proxy.type());
InetSocketAddress addr = (InetSocketAddress) proxy.address();
if (addr == null) {
System.out.println("No Proxy");
} else {
System.out.println("proxy hostname : " + addr.getHostName());
System.setProperty("http.proxyHost", addr.getHostName());
System.out.println("proxy port : " + addr.getPort());
System.setProperty("http.proxyPort", Integer.toString(addr.getPort()));
}
}
}
}
}
Basically in the code, if you clear the http.proxyHost and http.proxyPort and then set java.net.useSystemProxies to true, it will use
the system default proxy (if any) and ignore any VM arguments.
System.setProperty("http.proxyHost", "");
System.setProperty("http.proxyPort", "");
System.setProperty("java.net.useSystemProxies", "true");
System.out.println("detecting proxies");
Then you run this on your box and passed it some bogus proxy addresss:
C:\t>"C:\Program Files\Java\jdk1.6.0_19\bin\java.exe" -Dhttp.proxyHost=99.0.0.99.9 -Dhttp.proxyPort=8080 PrintDefaultProxy
detecting proxies
proxy Type : DIRECT
No Proxy
Note, if you do not clear those 2 properties, it will use the arguments you pass to the JVM – but from my understanding it’s not what your application seems to be doing. This is a way that the application should ‘just work’ without having to specifically set the proxyHost – and this is most likely why it ignores whatever setting you provide it at the JVM/Jboss level.
When the behaviour is consistent with what you’ve experienced trying to change those settings in Jboss, it means you can’t configure it in an application or Jboss level to use a proxyHost and most likely needs to be done at a Network level.

Java RMI connection to localhost at home network can't find correct remote module

I have been working on this project where two modules on different machines need to be in communication through RMI.
I start both client and server modules on my laptop. RMI seems to work correctly when i am at work and connected to work network, but when i am home, connected to my home network it does not work. It says remote object could not be found.
Here is the method i use at CLIENT side to get the reference to remote object
public static MyRMIApp getRemoteApp() throws RemoteException, NotBoundException, AccessException {
Registry registry = LocateRegistry.getRegistry("localhost", 28999); // tried 127.0.0.1 instead of localhost here, still not working
MyRMIApp app = (MyRMIApp) registry.lookup("COM");
return app;
}
Digging up a bit with some debugging, when i check the object value returned from getRemoteApp method, it shows me the end point is 67.215.65.132. Which is openDNS i am using to connect to internet. Shouldn't that be 127.0.0.1 ?
Then i used my mobile internet and tried again. It seems to be working but end-point is not 127.0.0.1 again it is the address assigned to me, which is 192.168.x.x
So can anybody please tell me what is wrong i am doing here ? I really would appreciate the help.
Oh and this is the piece of code at SERVER side
//Somwhere up top
private final static MyRMIApp rmiApp = new RMIServer();
//Down below
MyRMIApp stub = (MyRMIApp) UnicastRemoteObject.exportObject(rmiApp, 0);
Registry registry = LocateRegistry.createRegistry(28999);
registry.rebind("COM", stub);
See item A.1 of the RMI FAQ: specifically, 'The appropriate workaround is to set the system property java.rmi.server.hostname when starting the server.'

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