该代码实现了b+树的索引，插入与删除等功能，还具有快速查找的性能，并且算法时间复杂度性能较优.-The code to achieve the index b+ tree, insert and delete functions, but also has the capability to quickly find, and the algorithm time complexity better performance.

基于b树的文件索引，用java版实现。 。。。。。。。(A b-tree index file version, Java implementation.)