Help4j - Knowledge for Experts

Help4j is the largest, most comprehensive source of knowledge about the Java^tm programming language with more than 25 000 code examples, thousands of utility functions, tips and links. It seamlessly integrates with the standard API documentation. A click on a method or class and up to 20 code examples are at your fingertips.

Help4j greatly reduces the time spent searching for the right way to solve thousands of programming problems; it allows you to learn from other developers' code and keeps developers from reinventing the wheel. Help4j is unique because it is based on an extensive analysis of millions of lines of source code from hundreds of open source projects. If someone else has solved your problem before, it is most likely that Help4j has the solution for you!

Download Help4j Standard now (Free for non-commercial use) or browse the online version at http://www.help4j.org.

Features

• More than 25 000 code examples for classes from the J2SE^_TM platform.
• More than 1 000 open source utility functions and classes.
• Free for non-commercial use!
  
• Unmatched coverage: Help4j provides code examples for almost all commonly used methods from the J2SE platform and for many  rarely-used methods. In total, Help4j provides code examples for more than 8 000 distinct methods, constructors and fields from the J2SE platform. If you are not certain about using a class or method, look up the examples in Help4j!
• Four kinds of code examples for the Java language: 1) General examples about class usage, 2) examples about how an element is used, 3) example subclasses, 4) example interface implementations (where applicable).
• Open source examples: All code examples, utility functions etc. originate from open source projects which you can use for free, even in commercial products, provided that you adhere to the relevant licensing conditions.¹  
• Integrated with API documentation: Code examples and utility functions integrate seamlessly with the standard API documentation from Sun. You don't need to change your style of work: lookup an item in the API documentation and the examples are right there!
• Interactive Class Tab shows the structure of a class and accelerates access to all information and examples concerning its fields, constructors, methods, superclasses etc. Screenshot.
• Commonly used methods are shown first. Don't know which method you really need in a class? Help4j displays the most relevant methods first. For example, in java.sql.ResultSet, the three most frequently used methods are: next(), getString() and close(). If you browsed alphabetically  you would have had to examine more than 80 methods before reaching the next() method.
• Examples of subclasses and of interface implementations: See examples of how a subclass or interface is typically implemented. For example, see more than six source files demonstrating how to subclass javax.swing.DefaultListCellRenderer. In total more than 1 000 subclass examples are provided.
• Accelerated API documentation lookup. Lookup class entries in external API documentation by abbreviation. Instead of typing or browsing to ResultSet, just enter 'rs' and the information pops up.
• API Navigator provides rapid access to the 200 most frequently used classes of the J2SE platform.
• The Help4j programming reference contains more than 40 MByte of highly organized, easily accessible information for the Java language!
• Hundreds of notes, links and references.