Android学习之JSON 解析

JSONActivity.java:

package com.cz.json;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.PrintStream;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.Activity;
import android.os.Bundle;
import android.os.Environment;
import android.widget.TextView;

public class JSONActivity extends Activity {
	private String nameData[] = new String[] { "小王", "小李", "小张" };
	private int ageData[] = new int[] { 23, 25, 27 };
	private boolean isMarraiedData[] = new boolean[] { false, true, false };
	private double salaryData[] = new double[] { 7000.0, 5000.0, 3000.0 };
	private Date birthdayData[] = new Date[] { new Date(), new Date(),
			new Date() };
	private String companyName = "微软亚洲研究院";
	private String companyAddr = "中国北京";
	private String companyTel = "010-52354396";

	private TextView msg = null;

	/** Called when the activity is first created. */
	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);
		writeByJSON();
		readByJSON();

	}

	private void writeByJSON() {
		JSONObject jsonObject = new JSONObject(); // 建立最外面的节点对象
		JSONArray jsonArray = new JSONArray(); // 定义数组
		for (int x = 0; x < nameData.length; x++) { // 将数组内容配置到相应的节点
			JSONObject temp = new JSONObject(); // 每一个包装的数据都是JSONObject
			try {
				temp.put("name", this.nameData[x]);
				temp.put("age", this.ageData[x]);
				temp.put("married", this.isMarraiedData[x]);
				temp.put("salary", this.salaryData[x]);
				temp.put("birthday", this.birthdayData[x]);
			} catch (JSONException e) {
				e.printStackTrace();
			}
			jsonArray.put(temp); // 保存多个JSONObject
		}
		try {
			jsonObject.put("persondata", jsonArray);
			jsonObject.put("company", this.companyName);
			jsonObject.put("address", this.companyAddr);
			jsonObject.put("telephone", this.companyTel);
		} catch (JSONException e) {
			e.printStackTrace();
		}
		if (!Environment.getExternalStorageState().equals(
				Environment.MEDIA_MOUNTED)) { // 不存在不操作
			return; // 返回到程序的被调用处
		}
		File file = new File(Environment.getExternalStorageDirectory()
				+ File.separator + "xdwang" + File.separator + "json.txt"); // 要输出文件的路径
		if (!file.getParentFile().exists()) { // 文件不存在
			file.getParentFile().mkdirs(); // 创建文件夹
		}
		PrintStream out = null;
		try {
			out = new PrintStream(new FileOutputStream(file));
			out.print(jsonObject.toString()); // 将数据变为字符串后保存
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} finally {
			if (out != null) {
				out.close(); // 关闭输出
			}
		}

	}

	private void readByJSON() {

		this.msg = (TextView) super.findViewById(R.id.msg);

		if (!Environment.getExternalStorageState().equals(
				Environment.MEDIA_MOUNTED)) { // 不存在不操作
			return; // 返回到程序的被调用处
		}
		File file = new File(Environment.getExternalStorageDirectory()
				+ File.separator + "xdwang" + File.separator + "json.txt"); // 要输出文件的路径
		if (!file.exists()) { // 文件不存在
			return;
		}

		BufferedReader reader = null;
		String str = "";
		try {
			reader = new BufferedReader(new FileReader(file));
			String tempString = null;

			while ((tempString = reader.readLine()) != null) {
				str = str + tempString;
			}
			reader.close();
		} catch (Exception e) {
		} finally {
			if (reader != null) {
				try {
					reader.close();
				} catch (Exception e) {
				}
			}
		}

		StringBuffer buf = new StringBuffer();
		try {
			Map<String, Object> result = this.parseJson(str); // 解析文本
			buf.append("公司名称：" + result.get("company") + "\n");
			buf.append("电话号码：" + result.get("telephone") + "\n");
			buf.append("公司地址：" + result.get("address") + "\n");
			List<Map<String, Object>> all = (List<Map<String, Object>>) result
					.get("persondata");
			Iterator<Map<String, Object>> iter = all.iterator();
			while (iter.hasNext()) {
				Map<String, Object> map = iter.next();
				buf.append("姓名：" + map.get("name") + "，年龄：" + map.get("age")
						+ "\n" + "工资：" + map.get("salary") + "，是否结婚："
						+ map.get("married") + "\n" + "生日："
						+ map.get("birthday") + "\n");
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
		this.msg.setText(buf);
	}

	private Map<String, Object> parseJson(String data) throws Exception {
		Map<String, Object> maps = new HashMap<String, Object>();
		JSONObject jsonObject = new JSONObject(data); // 全部的内容变为一个项
		maps.put("company", jsonObject.getString("company")); // 取出项
		maps.put("telephone", jsonObject.getString("telephone")); // 取出项
		maps.put("address", jsonObject.getString("address")); // 取出项
		JSONArray jsonArray = jsonObject.getJSONArray("persondata"); // 取出数组
		List<Map<String, Object>> lists = new ArrayList<Map<String, Object>>();
		for (int x = 0; x < jsonArray.length(); x++) {
			Map<String, Object> map = new HashMap<String, Object>();
			JSONObject jsonObj = jsonArray.getJSONObject(x);
			map.put("name", jsonObj.getString("name"));
			map.put("age", jsonObj.getInt("age"));
			map.put("salary", jsonObj.getDouble("salary"));
			map.put("married", jsonObj.getBoolean("married"));
			map.put("birthday", jsonObj.getString("birthday"));
			lists.add(map);
		}
		maps.put("persondata", lists);
		return maps;
	}
}