In prior releases of JDeveloper, the Help menu included the J2SE API Reference:
Several customers asked us why it is missing from JDeveloper 10.1.3
The reason is that we don't include the J2SE API documentation in JDeveloper anymore.
Instead, we refer to http://java.sun.com/j2se/1.5.0/docs/api
If you want to add the JDK API locally:
- Download the Java Docs on your machine;
in my case, I keep it in C:\java\jdk1.5.0\doc\jdk-1_5_0-doc.zip
- In JDeveloper, select menu Tools > Manage Libraries... and click tab J2SE Definitions
- Select 1.5.0_05 library under User
- Click the 'Doc Path:' in the right panel and click button Add Entry...

- Expand C:\java\jdk1.5.0\doc\jdk-1_5_0-doc.zip!\docs, select api and click Select
Remark:
you don't need to extact the javadoc from the .zip file: you can
use this dialog to navigate within the .zip file and select the
directory holding the javadoc;
the path will be specified as the following: C:\java\jdk1.5.0\doc\jdk-1_5_0-doc.zip!\docs\api where the "!" separates the path to the zip file itself from the path to the javadoc within the .zip file.
- Ensure that C:\java\jdk1.5.0\doc\jdk-1_5_0-doc.zip!\docs\api
appears above the URL http://java.sun.com/j2se/1.5.0/docs/api by using
the arrow Move up
- Click OK
- Exit and restart JDeveloper
This won't add the menu J2SE API Reference in Help, but when you will select Go to Javadoc in java code, it will look at the local documentation instead of connectiing to http://java.sun.com
However, you can right-click the page and select Add to Favorites; by selecting menu Help -> Favorites, you'll then be able to access it directly.