PHPActivity.java

package www.wulian1.com.webview;

import android.content.SharedPreferences;import android.icu.text.IDNA;import android.os.Handler;import android.os.Message;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.util.Log;import android.view.View;import android.widget.Button;import android.widget.ListView;import android.widget.Toast;

import com.google.gson.Gson;import com.google.gson.reflect.TypeToken;

import org.json.JSONObject;import org.xml.sax.ErrorHandler;

import java.io.ByteArrayOutputStream;import java.io.IOException;import java.io.InputStream;import java.io.UnsupportedEncodingException;import java.net.HttpURLConnection;import java.net.URL;import java.util.List;

public class PHPActivity extends AppCompatActivity {

ListView listView;    List<StuManage> stuList=null;

private Handler handler = new Handler() {        @Override        public void handleMessage(Message msg) {            super.handleMessage(msg);            String abc = (String) msg.obj;            Toast.makeText(PHPActivity.this, "我输出的字符：" + abc, Toast.LENGTH_SHORT).show();            switch (msg.what) {                case 200:                    //获取到数据                    //List<StuManage> stuList=(List<StuManage>)msg.obj;                    if(stuList!=null &&stuList.size()>0) {                        MyAdapter myAdapter = new MyAdapter(stuList, PHPActivity.this);                        listView.setAdapter(myAdapter);                    }                    else                    {                        Toast.makeText(PHPActivity.this,"没有数据",Toast.LENGTH_SHORT).show();                    }                    break;                case 2:                    //获取失败                    Toast.makeText(PHPActivity.this,"获取数据失败",Toast.LENGTH_SHORT).show();                    break;                case 0:                    //获取发生异常                    Toast.makeText(PHPActivity.this,"获取数据异常",Toast.LENGTH_SHORT).show();                    break;                default:                    //其他情况                    Toast.makeText(PHPActivity.this,"获取数据异常2",Toast.LENGTH_SHORT).show();            }        }    };

@Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_php);

listView=(ListView)findViewById(R.id.lv_1);        SharedPreferences sp=this.getSharedPreferences("WebView",MODE_PRIVATE);        String dataString=sp.getString("name","");        if (!"".equals(dataString)){            Gson gson=new Gson();            try{                JSONObject jsonObject=new JSONObject(dataString);                String timestamp=jsonObject.getString("timestamp");                StuManage stuManage=gson.fromJson(dataString,StuManage.class);                Long nowtimestamp=System.currentTimeMillis();                Long offday=(nowtimestamp - stuManage.getTimestamp())/(1000*60*60*24);                Log.d("84","offday="+offday);                if (offday<30){                    //从缓存中获取数据                    dataget();                    Toast.makeText(PHPActivity.this,"未过期",Toast.LENGTH_SHORT).show();                    Log.d("84","距离上次天数为"+offday);                }else {                    getDataFromService();                    Toast.makeText(PHPActivity.this,"已过期",Toast.LENGTH_SHORT).show();                    Log.d("84","距离上次天数为"+offday);                }            }catch (Exception e){                e.printStackTrace();                Toast.makeText(PHPActivity.this,"获取时间异常",Toast.LENGTH_SHORT).show();                Log.d("84","获取时间异常");            }        }else {            //没拿到数据，重新获取数据            getDataFromCache();        }

Button btn_getstring = (Button) findViewById(R.id.btn_1);        Button btn_getjson = (Button) findViewById(R.id.btn_2);

btn_getjson.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                if (getDataFromCache()) {                    //拿到数据，绑定数据                    MyAdapter myAdapter=new MyAdapter(stuList,PHPActivity.this);                    listView.setAdapter(myAdapter);

Log.d("84","cache");                } else {                    getDataFromService();                    Log.d("84","Service");                }

//   Toast.makeText(PHPActivity.this,"准备完成",Toast.LENGTH_SHORT).show();            }        });    }

private void dataget() {        if (getDataFromCache()){            MyAdapter myAdapter=new MyAdapter(stuList,PHPActivity.this);            listView.setAdapter(myAdapter);        }else {            getDataFromService();        }    }

public String readInfoStream(InputStream input) throws Exception {        if (input == null) {            throw new Exception("输入流为null");        }        //字节数组        byte[] bcache = new byte[2048];        int readSize = 0;//每次读取的字节长度        int totalSize = 0;//总字节长度        ByteArrayOutputStream infoStream = new ByteArrayOutputStream();        try {            //一次性读取2048字节            while ((readSize = input.read(bcache)) > 0) {                totalSize += readSize;

//将bcache中读取的input数据写入infoStream                infoStream.write(bcache, 0, readSize);            }        } catch (IOException e1) {            throw new Exception("输入流读取异常");        } finally {            try {                //输入流关闭                input.close();            } catch (IOException e) {                throw new Exception("输入流关闭异常");            }        }

try {            return infoStream.toString("utf-8");        } catch (UnsupportedEncodingException e) {            throw new Exception("输出异常");        }    }

private boolean getDataFromCache() {        try {            SharedPreferences sharedPreferences = PHPActivity.this.getSharedPreferences("WebView", MODE_PRIVATE);            String data = sharedPreferences.getString("data", "");            //JSONObject jsonObject=new JSONObject(data);            //String code=jsonObject.get("code").toString();            if (data != "") {                // String datas=jsonObject.get("datas").toString();                Gson gson = new Gson();                stuList = gson.fromJson(data, new TypeToken<List<StuManage>>() {                }.getType());                return true;            } else {                stuList = null;                return false;            }        } catch (Exception e) {            e.printStackTrace();            stuList = null;            return false;        }    }

private void getDataFromService() {        final String path = "http://10.10.192.58:8081/Json/Json.php";        new Thread() {            @Override            public void run() {                super.run();                try {                    URL url = new URL(path);                    HttpURLConnection conn = (HttpURLConnection) url.openConnection();                    conn.setRequestMethod("GET");                    conn.setConnectTimeout(5000);                    Log.d("84", "try -1");                    int code = conn.getResponseCode();                    if (code == 200) {                        Log.d("84", "code==200");                        InputStream inputStream = conn.getInputStream();                        String abc = readInfoStream(inputStream);                        Gson gson = new Gson();                        stuList = gson.fromJson(abc, new TypeToken<List<StuManage>>() {                        }.getType());                        SharedPreferences sharedPreferences = getSharedPreferences("WebView", MODE_PRIVATE);                        SharedPreferences.Editor editor = sharedPreferences.edit();                        editor.putString("studata", abc);

//StuManage stuManage=new StuManage();                        //stuManage.setTimestamp(System.currentTimeMillis());                        //Gson gson=new Gson();

Log.d("84", "stulist 获取数据正常");                        Message message = new Message();                        message.obj = abc;                        message.what = 200;                        handler.sendMessage(message);                    } else {                        Message message = new Message();                        message.what = 2;                        handler.sendMessage(message);                        Log.d("84", "请求失败");                    }                } catch (Exception e) {                    Message message = new Message();                    message.what = 0;                    handler.sendMessage(message);                    Log.d("84", "Exception");                }            }        }.start();    }}