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Capturing HTTP traffic using Fiddler from Java applicaiton

I'm having difficulty using Fiddler to diagnose a problem in a Java application to connect to Microsoft Graph's API. Here's my basic environment:
JDK: 1.8.0_131
Apache HttpClient: 4.4
Fiddler: 4.6
The endpoint I'm trying to reach is https://login.microsoftonline.com/common/oauth2/authorize The problem I have is that the traffic is not captured by Fiddler.
I've tried various things as suggested by Googling for this problem, but have not got it to work. In my application, I set the proxy settings as follows:
httpClientBuilder.setProxy(new HttpHost(proxyServer, proxyPort, proxyScheme));
httpClientBuilder.build();
If I use ("127.0.0.1", 8888, "https"): then the error that I see is:
Unrecognized SSL message, plaintext connection?
If I use
("127.0.0.1", 8888, "http"): then the error that I see is: I/O
exception (org.apache.http.conn.UnsupportedSchemeException) caught
when processing request to
{tls}->http://127.0.0.1:8888->https://login.microsoftonline.com:443:
http protocol is not supported
I've tried other things (for example "localhost", "localhost.", and so on as suggested, and setting: -Djsse.enableSNIExtension=false), but so far no luck. Hopefully I am missing something obvious! Thanks for any help.

It turns out that the second configuration for the proxy is the correct one to use (using "http"), but what I had forgotten was that I was setting a ConnectionSocketFactoryRegistry in my HttpClientBuilder. I had not registered a ConnectionSocketFactory for "http" and this caused the second configuration to fail. I added this to the HttpClientBuilder, and now I can see traffic being captured by Fiddler:
connectionSocketFactoryRegistryBuilder.register("http", new PlainConnectionSocketFactory());

Remote access to ArangoDB through Java Interface

I have developed a Java application that uses ArangoDB as backend database (Used ArangoDB Java-Driver/Interface to access ArangoDB).
Everything is good until my ArangoDB and Application resides on same machine.
Once i moved ArangoDB to remote machine(Dedicated Server), my application is unable to access it :(
I have given my remote machine details(ArangoDB Server) in some properties file and feeding that file location to ArangoConfigure Constructor while creating ArangoDriver Object. But still i'm unable to access ArangoDB :(
Small snippet of my code is below:
protected static ArangoConfigure getConfiguration() {
//ArangoConfigure configure = new ArangoConfigure();
ArangoConfigure configure = new
ArangoConfigure("/Volumes/Official/ZLabs/arangodb.properties");
configure.init();
return configure; }
protected static ArangoDriver getArangoDriver(ArangoConfigure
configuration) { return new ArangoDriver(configuration); }
Please help me in this regard.
Awaiting your response.
Thanks & Best Regards,
- Mahi

First of all thank you #dothebart for all your help.
#dothebart, I have checked all the details that you have mentioned, before i posted here. Only thing is missed is HTTP connectivity thanks for pointing that.
Actually the below code change has fixed the problem for me.
Earlier code:
ArangoConfigure configure = new ArangoConfigure("/home/arango.properties");
configure.init();
ArangoDriver driver = new ArangoDriver(configuration);
Modified Code:
ArangoConfigure configure = new ArangoConfigure("/home/arango.properties");
ArangoHost hostObj = new ArangoHost(<IP-Address>, 8529);
configure.setArangoHost(hostObj);
configure.setUser(<user-name>);
configure.setPassword(<password>);
configure.init();
ArangoDriver driver = new ArangoDriver(configuration);
Setting up of host, username and password again is making it to work :(
File has all the details, then why should i provide them again.. I didn't understand that.
#dothebart i'm unable to find the log file, please let me know where can i find it.

If the Aranngodb Java driver fails to open or parse /Volumes/Official/ZLabs/arangodb.properties it issues a log message.
If arangodb properties looks like that:
port=8529
host=192.168.22.17
user=root
password=OpenSesame
enableCURLLogger=false
You start walking up the OSI model to debug TCP connection problems to evade possible connection issues due to firewals, routing etc.
One uses the commonly available telnet command to test the availability of the server:
telnet 192.168.22.17 8529
Trying 192.168.22.17...
If it sits there forever, you most probably have a firewall filtering you away, you finaly will get:
telnet: Unable to connect to remote host: Connection timed out
If it immediately exits with:
telnet: Unable to connect to remote host: Connection refused
It seems the server doesn't answer.
On the server side you then can check whether the service has bound the port (8529) you're trying to connect:
netstat -alpnt |grep 8529
tcp 0 0 0.0.0.0:8529 0.0.0.0:* LISTEN 19912/arangod
If you instead see it binding 127.0.0.1:8529 you won't be able to connect it remotely and need to change arangod.conf like this:
[server]
endpoint = tcp://0.0.0.0:8529
And then restart ArangoDB. Then, you should be able to see something like this:
telnet 192.168.22.17 8529
Trying 192.168.22.17...
Connected to 192.168.22.17.
Escape character is '^]'. <start to type now: >
GET / HTTP/1.0
<server should reply:>
HTTP/1.1 301 Moved Permanently
Location: /_db/_system/_admin/aardvark/index.html
Content-Type: text/html
Server: ArangoDB
Connection: Close
Content-Length: 197
<html><head><title>Moved</title></head><body><h1>Moved</h1>
<p>This page has moved to /_db/_system/_admin/aardvark/index.html.
</p></body></html>Connection closed by foreign host.

This looks like the properties-file isn't found in the classpath.
The path of the log-file should be configured in your log-configuration-file in your project.
Your project may use for example Logback (logback.xml) or another slf4j implementation.

Java resolve dns via proxy when using custom ProxySelector

I'm in need to develop a java library which allows a traffic to be directed via proxy only for specified hosts.
The library is almost ready and working, but there is problem with resolving dns addresses via proxy.
In short words I extended CustomProxySelector class which has following logic:
public class CustomProxySelector extends ProxySelector {
public List<Proxy> select(URI uri) {
if (customProxyDefinedFor(uri)) {
return getCustomProxyFor(uri);
} else {
// use direct connection
}
}
}
All works fine if local dns can resolve host given as "uri" parameter (for example if I want stackoverflow.com to go via proxy it will work because my local dns can resolve stackoverflow.com).
The problem comes when there is a host which is not known to my local dns. For example the dns behind proxy knows how to resolve address like "host1.private.dmz" because this is special host only known behind proxy (the proxy acts really as reverse proxy here). JVM seems to first try to resolve "host1.private.dmz" to ip, and when it fails it ends with folowing stacktrace:
Caused by: java.net.UnknownHostException: host1.private.dmz
at java.net.InetAddress.getAllByName0(InetAddress.java:1259)
at java.net.InetAddress.getAllByName(InetAddress.java:1171)
at java.net.InetAddress.getAllByName(InetAddress.java:1105)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:247)
(...)
Because it fails to resolve the ip, my Custom ProxySelector is never used. Is there any option to force java not to resolve ip via localdns but via proxy?
If I give the ip address of host1.private.dmz (for example 10.100.12.13) all works ok. The communication is directed to my Custom Proxy Selector and the traffic goes via custom proxy without problem.

I solved this issue. The important thing to fix this problem is correct understanding that the problem does not lay in jvm but in application. Jvm does not try to resolve host1.private.dmz before calling custom proxy selector, it is the application itself.
If we have a look at last line of the stacktrace you can see that exception comes from mysql jdbc driver, so it is mysql driver who trys to resolve host1.private.dmz to IP address, before actually opening connection to that host. Therefore because application does not open a connection (because exception occurs when application trys to resolve dns), no proxy selector is called ("no connection" == "no proxy selector").
What can we do in such case?
If it is you who writes the application, simply don't resolve the IP by calling InetAddress.getAllByName() and directly open connection to host domain name (host1.private.dmz). If for some reason you need an IP than handle the exception (in case of exception try to open connection without resolving the address). If still this is not acceptable for you there is one more option. You can instruct jvm to use extra DNS server which is able to resolve IP of this domain. You can do this by setting following properties:
System.setProperty("sun.net.spi.nameservice.provider.1", "dns,sun");
System.setProperty("sun.net.spi.nameservice.nameservers", "10.200.2.3,100.40.70.5);
This should set extra dns server for your application.
There can however be one more problematic situation. An attempt to resolve domain name to ip might take place before you have the chance to set up extra dns servers. For example you might be running web application on Tomcat with database connection pool configured in Tomcat's context. In such case the exception "UnknownHostException" can happen before you set up extra dnses. In such case you can run this application by "proxifying it". Strictly in java you can do this by using jProxyLoader library (http://jproxyloader.sourceforge.net) , for example by running the application with following parameters:
-Djava.system.class.loader=net.sf.jproxyloader.JProxyLoader -DjplDnsServers=10.0.1.18
Above example will set up 10.0.1.18 as extra dns server (which is able to resolve the uknown domain name) at application startup. Thanks to this extra dns will already be available when application boots up.
You understand more about this problem, by having a look at jProxyLoader troubleshooting page: http://jproxyloader.sourceforge.net/troubleshooting.html

Client Webservice in java - proxy authentication

I have made a web service client importing a third party wsdl in eclipse.
But I got this exception:
javax.xml.ws.WebServiceException: Connection IO Exception. Check nested exception for details. (Unable to connect to 1X.XXX.X.XX:X0 - Connection timed out).
I hope this exception occurred for the proxy only.
There is a proxy server between me and that third party. I don't know how to do the proxy authentication and where in coding I need to this proxy authentication.

Is your end point on HTTPS? There different ways proxies support HTTPS - one ways is SSL bridging and the other is SSL Tunneling..
May be your client side libraries you used to connect may not support the one being used by the proxy...

You must explicitly set the proxy server in Java, the JRE does not retrieve it from the OS configuration. You can find the detailed explanation here. As per the link, a standard configuration may look like this:
System.setProperty("http.proxyHost", "myproxy.com");
System.setPropery("http.proxyPort", "8080");
Obviously, you can also define the system properties as VM arguments during startup.

UnknkownHostException

Please help;
Am trying to deploy a web application.
The build is returning successful,and am not getting any errors on the sever.log
however am getting a http 503 error:the requested service() is not currently available
and also my
Java DB Database Process has this message
Warning: UnknkownHostException: intracare: intracare.
Could not listen on port 1527 on host localhost.
am using glassfish v3 prelude

Possibly you already have another application (perhaps another JavaDB instance?) listening on port 1527 - that could explain the "could not listen" message. Use netstat to check.

I think that UnknownHostException is related that intracare can't be resolved to an IP.
I would:
Ping that host.
Check C:\WINDOWS\system32\drivers\etc\hosts or /etc/hosts files.
Regards.

Check the DNS settings on the host. Your short names do not resolve correctly.

Mayby string you are typing as a host name is wrong? Maybe it is firewall problem?