Java keywords are listed in the Java language spec:

    Keyword: one of
            abstract    continue    for           new          switch
            assert      default     if            package      synchronized
            boolean     do          goto          private      this
            break       double      implements    protected    throw
            byte        else        import        public       throws
            case        enum        instanceof    return       transient
            catch       extends     int           short        try
            char        final       interface     static       void 
            class       finally     long          strictfp     volatile
            const       float       native        super        while

The keywords const and goto are reserved, even though they are not currently used. This may allow a Java compiler to produce better error messages if these C++ keywords incorrectly appear in programs.

While true and false might appear to be keywords, they are technically Boolean literals. Similarly, while null might appear to be a keyword, it is technically the null literal.