java数据结构和算法------索引查找

package iYou.neugle.search;

import java.util.ArrayList;
import java.util.List;

public class Index_search {
    class IndexItem {
        public int index;
        public int start;
        public int length;
    }

    public int m = 100;

    public int[] table = new int[] { 101, 102, 103, 104, 105, 201, 202, 203,
            204, 301, 302, 303 };

    public List<IndexItem> indexTable = new ArrayList<Index_search.IndexItem>();

    public static void main(String[] args) {
        Index_search index = new Index_search();
        // 创建索引
        index.CreateIndex();
        // 向索引表中插入数据
        index.InsertIndex(205);
        // 利用索引表查找数据
        int result = index.SearchIndex(205);
        System.out.println("索引位置为" + result);
    }

    public void CreateIndex() {
        int[] type = new int[10000];
        int[] typeNum = new int[10000];
        for (int i = 0; i < this.table.length; i++) {
            int n = this.table[i] / m - 1;
            if (type[n] == 0) {
                type[n] = 1;
            }
            typeNum[n]++;
        }
        int start = 0;
        for (int i = 0; i < typeNum.length; i++) {
            if (typeNum[i] == 0) {
                break;
            }
            IndexItem item = new IndexItem();
            item.index = i;
            item.start = start;
            item.length = typeNum[i];
            indexTable.add(item);
            start += typeNum[i];
        }
    }

    public void InsertIndex(int key) {
        int n = key / m - 1;
        int index = -1;
        // 更新索引表
        for (int i = 0; i < this.indexTable.size(); i++) {
            if (n == this.indexTable.get(i).index) {
                index = this.indexTable.get(i).start
                        + this.indexTable.get(i).length;
                this.indexTable.get(i).length++;
                break;
            }
        }

        for (int i = n + 1; i < this.indexTable.size(); i++) {
            this.indexTable.get(i).start++;
        }

        // 更新数组
        int[] temp = new int[this.table.length + 1];
        for (int i = 0; i < temp.length; i++) {
            if (i < index) {
                temp[i] = this.table[i];
            } else if (i == index) {
                temp[i] = key;
            } else {
                temp[i] = this.table[i - 1];
            }
        }

        this.table = temp;
    }

    public int SearchIndex(int key) {
        int n = key / m - 1;
        int start = -1;
        int length = -1;
        // 找到索引位置
        for (int i = 0; i < this.indexTable.size(); i++) {
            if (n == this.indexTable.get(i).index) {
                start = this.indexTable.get(i).start;
                length = this.indexTable.get(i).length;
                break;
            }
        }

        if (start == -1) {
            return -1;
        }
        // 从索引位置找数据
        for (int i = start; i < start + length; i++) {
            if (this.table[i] == key) {
                return i;
            }
        }
        return -1;
    }
}