A JavaScript tool that helps navigate the Java API documentation.

Developed and Copyright © 2002 - 2007 by Steve Claflin

About keyFinder

keyFinder enables fast searching of the class list in the lower left frame. It also provides for fast method searching, and hot-keys to jump to Fields, Constructors, Inner/Nested Classes, and Methods in the current class page.

Currently freeware – licensed freely for use on your own system, but not for distribution to others.

It works with the Sun JDK 1.3, 1.4, and 1.5 docs in IE5/6/7, Firefox, Netscape 4.7/8, and Mozilla 1.1 on most Windows versions Win98 and later, and I believe in Linux as well.

Jump to downloads.

Important Note

keyFinder will now work with the JDK 1.5 docs. There are several issues that you need to address, though:

Later versions do not necessarily support Netscape 4.7 – I now test only in IE6/7 and Firefox. I haven't tested other all combinations of JDK versions, earlier browser versions, operating systems, and other browsers such as Opera.

After installing the script, you can:

Type a class name or the first few letters and the lower left pane (the class hyperlink listing) will scroll to that item and highlight it. (In general, it will jump to whatever class it has identified as first match or, failing a match, the first one after the string you typed.) Use only lowercase letters; the Shift key is used in hot-key combinations listed below.

There is no text box – you just start pressing keys (or you can use the form-based approach, which provides a text box to type a name into).
If you type enough characters that you have reached the class you want, you can hit Enter and the right frame will change to that class page. If you got close, you can use the Up and Down arow keys to navigate up and down the list as well.

If you hit Shift-F, the right page will jump to the fields section, Shift-C will jump to constructors, Shift-M will jump to methods, and Shift-I or Shift-N will jump to inner (nested) classes.

Pressing the asterisk (*) key will switch to find methods mode, where your typing brings you to the methods list and scrolls to a method whose name matches what you typed. Pressing the asterisk again will return to find classes mode. There is no provision for finding overloaded versions of the same method name.

Pressing the asterisk again returns to normal mode. (Version 2.08 will make it clearer that you are in find methods mode by highlighting the selected method, and also enable UP and DOWN movement in the methods list.)

In IE, if you want to copy text from the page, you may need to pause the timer by pressing Shift-P. To resume normal operation, press Shift-P again. (Or, you can select text using the mouse, then use Ctrl-C wthout releasing the mouse button. That should achieve the copy and you can then release the mouse.)

Note that the script works on a timer – if you stop typing for a second it will reset (i.e., after a second it will start a new search rather than continue the current one). The time delay can be customized by changing the line that reads var keyTimeout = 1000; to use a different number (the number is in milliseconds, so 1000 = 1 second).
Also, sometimes you may have to wait a second or two and try again – there is additional code on a timer that refreshes the script so that the code works after switching class pages.

If you hit an incorrect character, hitting the Escape key will clear the finding process so you can start again (or you can wait for the automatic clearing based on keyTimeout).

You may also need to click on a blank spot within a page to initiate keyfinding, especially if you switched to a different application window and then returned. At one time I had the timer reset focus to the page, but that had annoying side effects.

To work with a package listing, select the package from the links in the upper left window. Then refresh the entire browser window. This should reinitialize keyFinder, but leave you on the package page.

Downloads and Version History

Zip files contain the JavaScript file, a modified version of this page, the optional form page, and several examples of how it can be installed into the index page. To work with JDK 1.5, you may need the file to repair the doc files.

Current Version: 2005-08-26 keyFinder 2.062 Now works in JDK 1.5.

Companion file: FixJavadocHtml

As noted above, potentially problematic in JDK 1.5 unless you run the FixJavadocHtml program from the docs/api directory. (It will compile in 1.4.2 or later; I haven't tested earlier JDK versions.)

Also fixed a bug that made it not work correctly in unsorted mode.

Note: from this point on, all versions will include the version information as part of the file name. Although that makes the instructions below dependent on the version you are using, it makes my life a lot easier since I don't have to worry about which version I actually included in the zip file.

Prior Versions

2004-11-20 keyFinder 2.06

Now works in Firefox; also fixed problems earlier versions had with Netscape 4.7/8.

Will not work correctly unless the class listing is sorted (even though JDK 1.5 reverted to the case-insensitive sort order).

2004-11-03 keyFinder 2.05

Improved fix for the August 2004 Windows XP security update.

Not recommended: 2.04 beta: download keyFinder 2.04 beta.

Quick fix for the August 2004 Windows XP security update. This has been tested minimally, but works on my system (it also seems a bit faster loading).

2.03 beta: download keyFinder 2.03 beta.

Does not work with August 2004 Windows XP SP2!

The 2.02 beta version is still available: download keyFinder 2.02 beta.

The 2.01 beta version is still available: download keyFinder 2.01 beta.

The 2.0 beta version is also still available: download keyFinder 2.0 beta.

The original version is also still available: download keyFinder 1.01.


  1. Unzip the file into the docs\api directory under your jdk directory. (You need the keyFinder.js file, and, if you wish to use the form based approach, keyFinderForm.html as well, in that location. The other html files are a copy of this file and examples of how to set up the form-based approach.)

  2. Then edit the index.html file in that directory by adding the following line in the <HEAD> section, under the </TITLE> line (note that the file name depends on the version – prior to 2.062 it was just keyFinder.js).:

    <script src="keyFinder2062.js"></script>

  3. Make the following edits, depending on whether you want a control frame or not:

Then you should be able to pull up the API index page and use the script to navigate through the class pages.

Give it a try – I'd be interested in any feedback or suggestions you might have.

Queued for development/enhancement:

  1. Almost finished – highlight method names in find methods mode and enable UP and DOWN arrow movement among methods; also, automatically leave find methods mode if another class link is exercised
  2. Improve the class list sort so that non-class links are not sorted into the middle of the list.
  3. Find a better solution for copying from the page for IE.
  4. Expand find methods capability to create an alphabetized list of all available methods, whether from the current class or one of its base classes. This would probably require an additional frame or pupup/hidden division that would be rewritten each time a new class page is loaded.
  5. Facility for adding your own notes to pages – (probably not going to happen in the near future).

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