Question

我正试图通过oauth访问twitter。因此，我注册了我的应用程序，下载了Twitter4j，在我的Eclipse-Project中添加了jar，然后尝试执行以下代码：

Twitter twitter = new TwitterFactory().getOAuthAuthorizedInstance("[key]","[secretKey]");
RequestToken requestToken = twitter.getOAuthRequestToken();
System.out.println(requestToken.getAuthorizationURL());

但它引发了以下异常：

[Sat May 29 11:19:11 CEST 2010]Using class twitter4j.internal.logging.StdOutLoggerFactory as logging factory.
[Sat May 29 11:19:11 CEST 2010]Use twitter4j.internal.http.alternative.HttpClientImpl as HttpClient implementation.
Exception in thread "main" java.lang.AssertionError: java.lang.reflect.InvocationTargetException
    at twitter4j.internal.http.HttpClientFactory.getInstance(HttpClientFactory.java:71)
    at twitter4j.internal.http.HttpClientWrapper.<init>(HttpClientWrapper.java:59)
    at twitter4j.http.OAuthAuthorization.init(OAuthAuthorization.java:83)
    at twitter4j.http.OAuthAuthorization.<init>(OAuthAuthorization.java:74)
    at twitter4j.TwitterFactory.getOAuthAuthorizedInstance(TwitterFactory.java:112)
    at MainProgram.main(MainProgram.java:18)
Caused by: java.lang.reflect.InvocationTargetException
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)
    at twitter4j.internal.http.HttpClientFactory.getInstance(HttpClientFactory.java:65)
    ... 5 more
Caused by: java.lang.NoClassDefFoundError: org/apache/http/impl/client/DefaultHttpClient
    at twitter4j.internal.http.alternative.HttpClientImpl.<init>(HttpClientImpl.java:63)
    ... 10 more

我目前无法弄清楚为什么......你能给我一些建议吗？

祝你好运菲利普

Answer 1

Caused by: java.lang.NoClassDefFoundError: org/apache/http/impl/client/DefaultHttpClient

您需要将apache http组件添加到类路径

Answer 2

因为我读'eclipse项目' - 如果这实际上是一个插件/ rcp项目并且你的库驻留在其他插件中，那么你必须通过plugin.xml导出所需的包，否则会导致NoClassDefFound错误。

Twitter4J在TwitterFactory中抛出异常

2 个答案: