Select the project in the package explorer. In the menu bar, click Project -> Generate Javadoc as shown below:



The dialog box shown below is displayed. You can leave the settings at their default values or change them as you like. In particular, you can change the javadoc destination directory. Click Next to go to the next step:



The following dialog box is displayed. You can change settings or leave them at their default values. Click Next to continue:



The dialog box shown below is displayed. Click Finish to generate the javadoc: