Eclipse 不会从 javadoc 位置提取工具提示.如果您说在浏览器中打开，则它仅使用 javadoc 位置来添加链接，您需要下载并附加 JDK 的源代码才能获得工具提示.对于 JRE 下的所有 JAR，javadoc 位置应该具有以下内容:http://java.sun.com/javase/6/docs/api/.对于 resources.jar、rt.jar、jsse.jar、jce.jar 和 charsets.jar，您应该附上可用的源 这里.

Eclipse doesn't pull the tooltips from the javadoc location. It only uses the javadoc location to prepend to the link if you say open in browser, you need to download and attach the source for the JDK in order to get the tooltips. For all the JARs under the JRE you should have the following for the javadoc location: http://java.sun.com/javase/6/docs/api/. For resources.jar, rt.jar, jsse.jar, jce.jar and charsets.jar you should attach the source available here.