Develop Reference

Request timeout with Java but working on cURL and postman

I'm setting up google recaptcha on my java application and I'm getting connect timeout:
Caused by: org.apache.http.conn.ConnectTimeoutException: Connect to www.google.com:443 [www.google.com/172.217.168.164] failed: connect timed out
at org.apache.http.impl.conn.HttpClientConnectionOperator.connect(HttpClientConnectionOperator.java:134)
at org.apache.http.impl.conn.PoolingHttpClientConnectionManager.connect(PoolingHttpClientConnectionManager.java:319)
at org.apache.http.impl.execchain.MainClientExec.establishRoute(MainClientExec.java:363)
at org.apache.http.impl.execchain.MainClientExec.execute(MainClientExec.java:219)
at org.apache.http.impl.execchain.ProtocolExec.execute(ProtocolExec.java:195)
at org.apache.http.impl.execchain.RetryExec.execute(RetryExec.java:86)
at org.apache.http.impl.execchain.RedirectExec.execute(RedirectExec.java:108)
at org.apache.http.impl.client.InternalHttpClient.doExecute(InternalHttpClient.java:184)
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:82)
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:106)
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:57)
at com.mashape.unirest.http.HttpClientHelper.request(HttpClientHelper.java:138)
HttpClientHelper.java:138
... 2 more
Caused by: java.net.SocketTimeoutException: connect timed out
at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:85)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
at java.net.Socket.connect(Socket.java:589)
at org.apache.http.conn.ssl.SSLConnectionSocketFactory.connectSocket(SSLConnectionSocketFactory.java:244)
at org.apache.http.impl.conn.HttpClientConnectionOperator.connect(HttpClientConnectionOperator.java:1
To test if there was any problem with the network, I made the same request using Postman and cURL, both returned the expected response. Then I used postman to generate java code, ran it and got the same error.
Notice that in order for the request to work with Postman I had to turn off "Use System Proxy". This lead me to think that maybe java was using system proxy by default and tried to disable it with System.setProperty("java.net.useSystemProxies", "false"); (also tried with true). Still got same error.
Here is a example of the code used:
HttpResponse<String> response = Unirest.post("https://www.google.com/recaptcha/api/siteverify")
.header("response", "abc")
.header("secret", "abc")
.asString();
Thanks in advance.

Like so often, the reason was dead simple:
The target server only has an IPv4 address. Java for some reason tries to access the target using IPv6 and fails to do so. I assume that this kind of "halts" the ongoing process and this can only be remedied by aborting the hanging thread (what the timeout effectively does)
As soon as I addded -Djava.net.preferIPv4Stack=true to the call of my program, I was able to run it successfully.
source: HttpClient hits timeout but server is available and working flawlessly
maybe?

What's the difference between Windows and Linux/OS X when using the Java SSLSocket?

I wrote a multi-server chat system based on Java under Windows. At the security part, I created one keystore to create the SSLSocket. When I launch 3 servers, it works on Windows(Win10 14393.321) but fails on OS X(Version 10.12 (16A323)) and Linux(Ubuntu 14.04.4 LTS). It really confused me. Here is the keystore part:
System.setProperty("javax.net.ssl.keyStore",keyFilepath);
System.setProperty("javax.net.ssl.trustStore",keyFilepath);
System.setProperty("javax.net.ssl.keyStorePassword","password");
System.setProperty("javax.net.ssl.trustStorePassword", "password");
And when I run the third server on OS X or Linux, it shows:
java.net.ConnectException: Connection refused
at java.net.PlainSocketImpl.socketConnect(Native Method) at
java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
at
java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
at
java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) at
java.net.Socket.connect(Socket.java:589) at
sun.security.ssl.SSLSocketImpl.connect(SSLSocketImpl.java:668) at
sun.security.ssl.SSLSocketImpl.(SSLSocketImpl.java:427) at
sun.security.ssl.SSLSocketFactoryImpl.createSocket(SSLSocketFactoryImpl.java:88)
at server.AuthorizeServer.MessageReceive(AuthorizeServer.java:99) at
server.AuthorizeServer.main(AuthorizeServer.java:64) at
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497) at
org.eclipse.jdt.internal.jarinjarloader.JarRsrcLoader.main(JarRsrcLoader.java:58)
This is my first time asking on StackOverflow and I really looking forward to your kind help.
Thanks!

java.net.ConnectException: Connection refused
Connection refused is an error message from the TCP stack and means that it could not connect with TCP to the other side. Since SSL/TLS is a layer on top of TCP and is only started once the TCP connect succeeded it means that the problem is not caused by different behavior at the SSL/TLS layer.
That this is not cause by the SSL layer but the TCP layer can also be seen by the stacktrace: Connection refused at java.net.PlainSocketImpl.socketConnect
More likely is that there is something blocking the TCP connection (firewall) or that you've tried to listen/connect to the wrong IP address (e.g. trying to reach a server listening on 127.0.0.1 on Windows from the Linux system). But is impossible to say from the currently provided information what exactly is the case.

JVM appears to cache failed DNS lookups even if caching is "disabled"

I have basically the same problem explained here:
Keep getting java.net.UnknownHostException after connecting to the internet
The problem is following, when my java application starts without Internet connection, it will forever continue throwing UnknownHostException, even in the casse when Internet connection is established.
The stack trace is quite huge:
javax.xml.ws.WebServiceException: Failed to access the WSDL at: http://www.taxifcd.de/DebugWirelessDataWebService/wdws?wsdl. It failed with:
www.taxifcd.de.
at com.sun.xml.internal.ws.wsdl.parser.RuntimeWSDLParser.tryWithMex(RuntimeWSDLParser.java:250)
at com.sun.xml.internal.ws.wsdl.parser.RuntimeWSDLParser.parse(RuntimeWSDLParser.java:231)
at com.sun.xml.internal.ws.wsdl.parser.RuntimeWSDLParser.parse(RuntimeWSDLParser.java:194)
at com.sun.xml.internal.ws.wsdl.parser.RuntimeWSDLParser.parse(RuntimeWSDLParser.java:163)
at com.sun.xml.internal.ws.client.WSServiceDelegate.parseWSDL(WSServiceDelegate.java:348)
at com.sun.xml.internal.ws.client.WSServiceDelegate.<init>(WSServiceDelegate.java:306)
at com.sun.xml.internal.ws.client.WSServiceDelegate.<init>(WSServiceDelegate.java:215)
at com.sun.xml.internal.ws.client.WSServiceDelegate.<init>(WSServiceDelegate.java:196)
at com.sun.xml.internal.ws.client.WSServiceDelegate.<init>(WSServiceDelegate.java:192)
at com.sun.xml.internal.ws.spi.ProviderImpl.createServiceDelegate(ProviderImpl.java:104)
at javax.xml.ws.Service.<init>(Service.java:77)
at de.dlr.ts.wirelessdata.ws.client.WirelessDataWebServiceImplService.<init>(WirelessDataWebServiceImplService.java:42)
at de.dlr.ts.wirelessdata.ws.client.WirelessDataWebServiceClient.<init>(WirelessDataWebServiceClient.java:62)
at de.dlr.dynamic.client.core.impl.bam.BAMImpl$PacketSender.init(BAMImpl.java:500)
at de.dlr.dynamic.client.core.impl.bam.BAMImpl$PacketSender.run(BAMImpl.java:534)
Caused by: java.net.UnknownHostException: www.taxifcd.de
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:184)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
at java.net.Socket.connect(Socket.java:589)
at java.net.Socket.connect(Socket.java:538)
at sun.net.NetworkClient.doConnect(NetworkClient.java:180)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:432)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:527)
at sun.net.www.http.HttpClient.<init>(HttpClient.java:211)
at sun.net.www.http.HttpClient.New(HttpClient.java:308)
at sun.net.www.http.HttpClient.New(HttpClient.java:326)
at sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLConnection.java:1169)
at sun.net.www.protocol.http.HttpURLConnection.plainConnect0(HttpURLConnection.java:1105)
at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:999)
at sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:933)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1513)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1441)
at java.net.URL.openStream(URL.java:1045)
at com.sun.xml.internal.ws.wsdl.parser.RuntimeWSDLParser.createReader(RuntimeWSDLParser.java:984)
at com.sun.xml.internal.ws.wsdl.parser.RuntimeWSDLParser.resolveWSDL(RuntimeWSDLParser.java:385)
at com.sun.xml.internal.ws.wsdl.parser.RuntimeWSDLParser.parse(RuntimeWSDLParser.java:216)
... 13 more
If I run program with Internet connection and after some time disconnect and connect it works good. I tried also with changing caching parameters of the network like this:
java.security.Security.setProperty("networkaddress.cache.ttl" , "0");
java.security.Security.setProperty("networkaddress.cache.negative.ttl" , "0");
But that also didn't help. Any idea how to solve this? It is obvious to me that the problem is in Java not recognizing the change on the network.

Socket closed error while performing load testing on jmeter

I am trying to run my load test on jmeter for REST api which is returning JSON.
I am passing the following header information in Header manager
Authorization: Bearer VHFAJ0dxNQfJlzPmr7miaH4QOFeNVmez6RXVHX59uovrFAL6z5zMv9krpBAvOcNTwqHRFa8REaidlpuJSUMF8Ol38t7n-sHP2WQn0KmrEnFrtdo6XDRdhspVP1D72oIlu9sP_-rdv1MdsnakVewqrzZ9PeDiWhVKqRBTjWVlnZFpLS-CZ86DFanQ9cw7VZ67a1yOWC7_os7vZYeIhaQ8dM_8n_ocYzFDcCHELSGqnz3NHc9DRrQQfjM6xB17aRjUKQ4ZNV52Ss_1BKG8-5H7bMpi1QiAdDS17K55WrNAZMzgHeaP6UwtQwJyo_gxiaW5PlNJZNQQn4rZvNkIRd_V9Q
Content-Type: application/x-www-form-urlencoded
Accept: application/json
Few days ego I tried the same test on local internal server and it was working fine. Now I am running this on UAT env which is setup on AWS.
This is working fine with chrome Postman extension.
Also I have followed the below link but no success and getting the socket closed exception
Non HTTP response message: The target server failed to respond: Is my server failing to handle load
java.net.SocketException: Socket closed
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
at java.net.Socket.connect(Socket.java:589)
at org.apache.http.conn.scheme.PlainSocketFactory.connectSocket(PlainSocketFactory.java:127)
at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:180)
at org.apache.http.impl.conn.ManagedClientConnectionImpl.open(ManagedClientConnectionImpl.java:294)
at org.apache.jmeter.protocol.http.sampler.MeasuringConnectionManager$MeasuredConnection.open(MeasuringConnectionManager.java:107)
at org.apache.http.impl.client.DefaultRequestDirector.tryConnect(DefaultRequestDirector.java:643)
at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:479)
at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:906)
at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:805)
at org.apache.jmeter.protocol.http.sampler.HTTPHC4Impl.executeRequest(HTTPHC4Impl.java:517)
at org.apache.jmeter.protocol.http.sampler.HTTPHC4Impl.sample(HTTPHC4Impl.java:331)
at org.apache.jmeter.protocol.http.sampler.HTTPSamplerProxy.sample(HTTPSamplerProxy.java:74)
at org.apache.jmeter.protocol.http.sampler.HTTPSamplerBase.sample(HTTPSamplerBase.java:1146)
at org.apache.jmeter.protocol.http.sampler.HTTPSamplerBase.sample(HTTPSamplerBase.java:1135)
at org.apache.jmeter.threads.JMeterThread.process_sampler(JMeterThread.java:434)
at org.apache.jmeter.threads.JMeterThread.run(JMeterThread.java:261)
at java.lang.Thread.run(Thread.java:745)
Please let me know if more information is required

If your UAT deployment is behind Elastic Load Balancer or Elastic IP it may be the situation when JMeter resolves IP address of only one server and it becomes overloaded while others are idle.
Try adding DNS Cache Manager to your Test Plan to see if it helps. Check out The DNS Cache Manager: The Right Way To Test Load Balanced Apps guide for more information on the domain.

You should read this:
https://wiki.apache.org/jmeter/JMeterSocketClosed
Note Socket closed can be an issue with your server.

MySql with JAVA error. The last packet sent successfully to the server was 0 milliseconds ago [duplicate]

This question already has answers here:
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
(51 answers)
Closed 4 years ago.
I have read about this exception a lot, but I can't solve my.
Mysql server is working.
I can connect to it from NetBeans, but I can't connect to it from java code.
Exception in thread "main" com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:525)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1116)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:344)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2332)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2369)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2153)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:792)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:525)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:381)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:305)
at java.sql.DriverManager.getConnection(DriverManager.java:579)
at java.sql.DriverManager.getConnection(DriverManager.java:243)
at javaapplication3.JavaApplication3.main(JavaApplication3.java:32)
Caused by: java.net.SocketException: Permission denied: connect
at java.net.DualStackPlainSocketImpl.connect0(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:69)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:339)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:200)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:182)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:157)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:391)
at java.net.Socket.connect(Socket.java:579)
at java.net.Socket.connect(Socket.java:528)
at java.net.Socket.<init>(Socket.java:425)
at java.net.Socket.<init>(Socket.java:241)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:257)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:294)
... 15 more
Java Result: 1
I catch this exception with any ways to connect to Mysql from java code, but from MysqlWorkBench and from NetBeans is OK.
I have no Firewall. I tried 127.0.0.1, result is the same.

Search the file my.cnf and comment the line
skip-networking
to
#skip-networking
Restart mysql

Try to specify the port in
conn = DriverManager.getConnection("jdbc:mysql://localhost/mysql?"
+ "user=root&password=onelife");
I think you should have something like this:
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/mysql?"
+ "user=root&password=onelife");
Also, the port number in my example (3306) is the default port, but you may change it while installing MySQL.
I think that a better way to specify password and user is to separate them from the URL like this:
connection = DriverManager.getConnection(url, login, password);

THis issue has been fixed with new mysql connectors,
please use http://mvnrepository.com/artifact/mysql/mysql-connector-java/5.1.38
I used to get this error after updating the connector jar, issue resolved.

The problem is mostly due to a MySQL service that is not running, so make sure it is. If it isn't, run this CMD with administrator privilege in order to start it:
sc start [Your MySQL Service name]

Try the following suggestions:
Your machine may have a static IP; map this IP to the hosts file as localhost.
Try to log in from your computer or within the network via mysql command; if login is successful, it means that MySQL runs fine.

There are two things
Disable firewall if any or add exception or check if u have correct driver file. Disable any antivirus if any
and also make sure your driver type is mysql.jdbc.driver.

It seems that your Java code is using IPv6 instead of IPv4. Please try to use 127.0.0.1 instead of localhost. Ex.: Your connection string should be
jdbc:mysql://127.0.0.1:3306/expeditor?zeroDateTimeBehavior=convertToNull&user=root&password=onelife
P.S.: Please update the URL connection string.