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Test of java SSL / keystore / cert setup. Check the commet #1 for howto.
/** Establish a SSL connection to a host and port, writes a byte and
* prints the response. See
public class SSLPoke {
public static void main(String[] args) {
if (args.length != 2) {
System.out.println("Usage: "+SSLPoke.class.getName()+" <host> <port>");
try {
SSLSocketFactory sslsocketfactory = (SSLSocketFactory) SSLSocketFactory.getDefault();
SSLSocket sslsocket = (SSLSocket) sslsocketfactory.createSocket(args[0], Integer.parseInt(args[1]));
InputStream in = sslsocket.getInputStream();
OutputStream out = sslsocket.getOutputStream();
// Write a test byte to get a reaction :)
while (in.available() > 0) {
System.out.println("Successfully connected");
} catch (Exception exception) {

Test of java SSL / keystore / cert setup. Came from


  1. extract cert from server:
    openssl s_client -connect server:443

  2. negative test cert / keytool:
    java SSLPoke server 443
    you should get something like PKIX path building failed: unable to find valid certification path to requested target

  3. import cert into default keytool:
    keytool -import -alias -keystore $JAVA_HOME/jre/lib/security/cacerts

  4. positive test cert / keytool:
    java SSLPoke server 443
    you should get this:
    Successfully connected


Thanks! Helped us to debug a cert issue.


Doesn't seems work as I thought it should work. it doesn't check if the server certificate is matching with the parameter.


java SSLPoke ip.address.of.sslserver 443
Successfully connected

So it doesn't really check the certificate?


@jackchen858 +1 It does not


It did not work for me.

I always get Successfully connected msg


Make sure you run this with the right java in case you have multiple installations


Works brilliantly. Thanks


Thanks a lot. Followed your instructions. Fix worked perfectly.

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