Java was conceived by James Gosling, Patrick Naughton, Chris Warth and Mike Sheridan at Sun Microsystems inc. in 1991. It was an effort of 18 months to develop the first working version. The language was initially named as Oak in the fall of 1992 but later it was renamed as Java in 1995.

It is believed that the main strength of Java is platform independence. The main disadvantages of C and C++ are that they are designed to be compiled for specific target. It is possible to compile C++ program for just any type of CPU, but it requires a full compiler targeted for the CPU. One more strong point of Java is its uniqueness to conquer World Wide Web.

More Source: The Java History Timeline, Sun Java Blog