How to use API keys for Google cloud Translate API

I am trying to use Google cloud translate API in Java. I have signed up free trial version and enable translate API project from google cloud console. Also I have API key with me.

I referred to API usage reference created java maven project included dependency of google-cloud-translate. Its downloaded also as a dependency. In java class file I am using same code as given the link but its giving me below error.

I have not used API keys anywhere as I don't know where to use it. I think that's the problem but don't know how to pass API keys for authentication? So I missed step "gcloud beta auth application-default login" in the link as running it on command line doesn't work.

I have java project in eclipse and I am using "Run As"-> "Java application" to run it.

    Exception in thread "main" com.google.cloud.translate.TranslateException: connect timed out
    at com.google.cloud.translate.spi.DefaultTranslateRpc.translate(DefaultTranslateRpc.java:63)
    at com.google.cloud.translate.spi.DefaultTranslateRpc.translate(DefaultTranslateRpc.java:145)
    at com.google.cloud.translate.TranslateImpl$4.call(TranslateImpl.java:113)
    at com.google.cloud.translate.TranslateImpl$4.call(TranslateImpl.java:110)
    at com.google.cloud.RetryHelper.doRetry(RetryHelper.java:179)
    at com.google.cloud.RetryHelper.runWithRetries(RetryHelper.java:244)
    at com.google.cloud.translate.TranslateImpl.translate(TranslateImpl.java:110)
    at com.google.cloud.translate.TranslateImpl.translate(TranslateImpl.java:124)
    at com.translate.main.Translator.main(Translator.java:83)
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:345)
    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 sun.security.ssl.SSLSocketImpl.connect(SSLSocketImpl.java:656)
    at sun.net.NetworkClient.doConnect(NetworkClient.java:175)
    at sun.net.www.http.HttpClient.openServer(HttpClient.java:432)
    at sun.net.www.http.HttpClient.openServer(HttpClient.java:527)
    at sun.net.www.protocol.https.HttpsClient.<init>(HttpsClient.java:275)
    at sun.net.www.protocol.https.HttpsClient.New(HttpsClient.java:371)
    at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(AbstractDelegateHttpsURLConnection.java:191)
    at sun.net.www.protocol.http.HttpURLConnection.plainConnect0(HttpURLConnection.java:1104)
    at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:998)
    at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:177)
    at sun.net.www.protocol.https.HttpsURLConnectionImpl.connect(HttpsURLConnectionImpl.java:153)
    at com.google.api.client.http.javanet.NetHttpRequest.execute(NetHttpRequest.java:93)
    at com.google.api.client.http.HttpRequest.execute(HttpRequest.java:972)
    at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.executeUnparsed(AbstractGoogleClientRequest.java:419)
    at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.executeUnparsed(AbstractGoogleClientRequest.java:352)
    at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.execute(AbstractGoogleClientRequest.java:469)
    at com.google.cloud.translate.spi.DefaultTranslateRpc.translate(DefaultTranslateRpc.java:125)
    ... 7 more

Solution

Couple of things that helped me out:

Used my api key as below:

Translate translate = TranslateOptions.newBuilder().
setApiKey((String)PropertyLoader.prop.get("GOOGLE_API_KEY")).
build().getService();

I was running the code behind corporate proxy(silly me). I added below lines(a static initializer) to my java code and bingo !!!

static {
    System.setProperty("http.proxyHost", HTTP_PROXY_HOST);
    System.setProperty("http.proxyPort", HTTP_PROXY_PORT);
    System.setProperty("https.proxyHost", HTTPS_PROXY_HOST);
    System.setProperty("https.proxyPort", HTTPS_PROXY_PORT);
}

where HTTP_PROXY_HOST and others are defined constants for my company...