利用Java程序将字符串进行排序与拼接

1、初始生成字符串的代码程序：

package com.map.test;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class Test {

	/**
	 * @param args
	 */
	public static List<Map<String, String>> maps = new ArrayList<Map<String,String>>();
	static{
		
		Map m1 = new HashMap<String, String>();
		m1.put("total", "10");
		m1.put("createTime", "2014-10-18");
		maps.add(m1);
		Map m2 = new HashMap<String, String>();
		m2.put("total", "20");
		m2.put("createTime", "2014-10-15");
		maps.add(m2);
		Map m3 = new HashMap<String, String>();
		m3.put("total", "30");
		m3.put("createTime", "2014-10-19");
		maps.add(m3);
		Map m4 = new HashMap<String, String>();
		m4.put("total", "40");
		m4.put("createTime", "2014-10-17");
		maps.add(m4);
		Map m5 = new HashMap<String, String>();
		m5.put("total", "50");
		m5.put("createTime", "2014-10-16");
		maps.add(m5);
		Map m6 = new HashMap<String, String>();
		m6.put("total", "60");
		m6.put("createTime", "2014-10-20");
		maps.add(m6);
		Map m7 = new HashMap<String, String>();
		m7.put("total", "70");
		m7.put("createTime", "2014-10-21");
		maps.add(m7);
	}

2、main方法调用拼接的方法

public static void main(String[] args) {
		// TODO Auto-generated method stub
		sortList(maps);
		getTimeString();
		getTotalString();

	}

3、将程序进行排序

package com.map.test;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Comparator;
import java.util.Date;
import java.util.Map;

public class ReportCompare implements Comparator<Map<String, String>> {

	@Override
	public int compare(Map<String, String> o1, Map<String, String> o2) {
		String o1Time = o1.get("createTime");
		String o2Time = o2.get("createTime");
		SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
		try {
			Date o1D = sdf.parse(o1Time);
			Date o2D = sdf.parse(o2Time);
			if (o1D.before(o2D)) {
				return -1;
			}else if (o1D.equals(o2D)) {
				return 0;
			}else if (o1D.after(o2D)) {
				return 1;
			}
		} catch (ParseException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return 2;
	}

}

4、拼接字符串

public static void getTimeString() {
		StringBuffer sb = new StringBuffer("[");
		for (Map<String, String> map : maps) {
			sb.append("'"+map.get("createTime")+"',");
		}
		sb.deleteCharAt(sb.length()-1);
		sb.append("]");
		System.out.println(sb.toString());
	}
	public static void getTotalString() {
		StringBuffer sb = new StringBuffer("[");
		for (Map<String, String> map : maps) {
			sb.append(map.get("total")+",");
		}
		sb.deleteCharAt(sb.length()-1);
		sb.append("]");
		System.out.println(sb.toString());
	}
	public static List<Map<String, String>> sortList(List<Map<String, String>> maps){
		 Collections.sort(maps, new ReportCompare());
		 return maps;
	}

}