安卓开发前后台通信,从数据库中取数据并在前台以表格形式显示,以json格式传输

Posted 文战武谏

tags:

篇首语:本文由小常识网(cha138.com)小编为大家整理,主要介绍了安卓开发前后台通信,从数据库中取数据并在前台以表格形式显示,以json格式传输相关的知识,希望对你有一定的参考价值。

最近做了一个android开发小demo,主要功能是在手机的ActionBar中的搜索栏,根据用户输入的名字从后台(java+Tomcat)数据库中取出该名字对应的一系列信息,然后通过json形式传到前台,并用表格的形式显示到前台。
跟大家分享一下,并且列出几个比较坑的点。但是只是列出了java文件和layout中的xml文件,drawable以及bean类没有列
涉及的知识点主要有:

  • 利用HttpUrlConnection进行通信
  • 数据库相关操作
  • 利用json传输数据
  • 后台代码的mvc模式
  • Android中用列表显示数据(表格是自己画的)

前台

前台主要涉及两个Activity,一个是SearchActivity,一个是SearchResultActivity。

SearchActivity

SearchActivity,它的主要功能是在ActionBar中的搜索栏可以接收用户输入的数据,并且可以动态提示,点击回车后,会将数据传到SearchResultActivity。
话不多说,上代码:

package com.wzy.search.aty;

import java.util.ArrayList;

import com.wzy.search.R;
import android.annotation.SuppressLint;
import android.app.ActionBar;
import android.app.Activity;
import android.app.SearchManager;
import android.app.SearchableInfo;
import android.content.ComponentName;
import android.content.Context;
import android.graphics.Color;
import android.opengl.Visibility;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.inputmethod.EditorInfo;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.SearchView;
import android.widget.SearchView.OnCloseListener;
import android.widget.SearchView.OnQueryTextListener;
import android.widget.TextView;

/**
 * 该Activity执行前台搜索功能,具备自动提示
 * @author wzy
 * @version V1.0
 */
@SuppressLint("DefaultLocale")
public class SearchActivity extends Activity {

    SearchView searchView = null;
    EditText searchText = null;        
    private ListView searchListView = null; 
    private ArrayAdapter<String> searchAdapter = null;
    private String[] searchNames = null; 
    private ArrayList<String> searchList = null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.search_person);

        ActionBar actionBar = getActionBar();
        if (actionBar != null) {
            actionBar.setDisplayHomeAsUpEnabled(true);  // 给左上角图标左边加上一个返回图标
        }

        searchListView = (ListView) findViewById(R.id.searchListView);

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {     

        // 自定义菜单,设置搜索栏
        getMenuInflater().inflate(R.menu.search_menu, menu);
        //获取SearchView对象
        searchView = (SearchView) menu.findItem(R.id.search).getActionView();
        if (searchView == null) {
            Log.e("SearchView", "Fail to get Search");
            return true;
        }

        // 获得searchview文本对象
        int search_text_id = searchView.getContext().getResources().getIdentifier("android:id/search_src_text", null, null);
        searchText = (EditText) searchView.findViewById(search_text_id);

        searchView.setOnSearchClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                searchListView.setVisibility(View.VISIBLE);
            }
        });

        searchView.setOnCloseListener(new OnCloseListener() {

            @Override
            public boolean onClose() {
                // TODO Auto-generated method stub
                searchListView.setVisibility(View.INVISIBLE);
                return false;
            }
        });     

        searchNames = new String[]{"abc","bcd","cde","def","efg","wxy","xyz"};
        searchAdapter = new ArrayAdapter<String>(getApplicationContext(), android.R.layout.simple_expandable_list_item_1,searchNames);

        searchListView.setAdapter(searchAdapter);
        searchListView.setTextFilterEnabled(true);

        searchListView.setOnItemClickListener(new OnItemClickListener() {

            @Override 
            public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
                // TODO Auto-generated method stub
                searchText.setText(((TextView)arg1).getText().toString());
                searchText.setSelection(((TextView)arg1).getText().toString().length());
                Log.e("string", ((TextView)arg1).getText().toString());
            }

        });

        searchView.setOnQueryTextListener(new OnQueryTextListener() {

            @Override
            public boolean onQueryTextSubmit(String query) {
                // TODO Auto-generated method stub
                return false;
            }

            @Override
            public boolean onQueryTextChange(String newText) {
                // TODO Auto-generated method stub
                if (newText.length() != 0) {
                    setFilterText(newText);
                } else {
                    clearTextFilter();
                }
                return false;
            }
        });

        //设置搜索图标。设置为false的时候icon固定于文字左边,设置为true在文字右边,随文字动
        searchView.setIconified(true);

        //获取SearchView文本对象

        searchText.setTextColor(Color.WHITE);
        //核心代码
        //获取搜索服务管理器
        SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
        // searchable activity的component name,由此系统可通过intent进行唤起
        ComponentName componentName = new ComponentName(this, SearchResultActvity.class);
        // 通过搜索管理器,从searchable activity中获取相关搜索信息,就是searchable的xml设置。如果返回null,表示该activity不存在,或者不是searchable
        SearchableInfo searchableInfo = searchManager.getSearchableInfo(componentName);
        if (searchableInfo == null) {
            Log.e("SearchableInfo", "Fail to get SearchableInfo");
        }
        // 将searchable activity的搜索信息与search view关联
        searchView.setSearchableInfo(searchableInfo);
        return true;
    }

    @SuppressLint("DefaultLocale")
    public void setFilterText(String filterText) {
        ArrayList<String> list = new ArrayList<String>();
        String[] tempStr;
        for (int i = 0; i < searchNames.length; i++) {

            String searchNameIgnoreCase = searchNames[i].toLowerCase();
            String filterTextIgnoreCase = filterText.toLowerCase();
            if (searchNameIgnoreCase.contains(filterTextIgnoreCase)) {
                list.add(searchNames[i]);
            }
        }
        if (list.size() >= 0) {
            tempStr = new String[list.size()];
            int j = 0;
            for (String str : list) {
                tempStr[j++] = str;
            }
            searchAdapter = new ArrayAdapter<String>(getApplicationContext(),
                    android.R.layout.simple_expandable_list_item_1, tempStr);
            searchListView.setAdapter(searchAdapter);
        }
    }

    public void clearTextFilter() {
        searchAdapter = new ArrayAdapter<String>(getApplicationContext(),
                android.R.layout.simple_expandable_list_item_1, searchNames);
        searchListView.setAdapter(searchAdapter);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // TODO Auto-generated method stub
        switch (item.getItemId()) {
        case android.R.id.home:
            overridePendingTransition(R.anim.tran_return_in, R.anim.tran_return_out);
            finish();
            break;

        case R.id.search:

            break;

        default:
            break;
        }
        return super.onOptionsItemSelected(item);
    }

    long lastClickTime = 0;
    @Override
    public void onBackPressed() {
        overridePendingTransition(R.anim.tran_return_in, R.anim.tran_return_out);
        finish();
    }
}

search_person.xml如下:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <ListView
        android:id="@+id/searchListView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:visibility="invisible"
        android:background="#454545"/>
</LinearLayout>

SearchResultActivity

上面的代码就把数据传到SearchResultActivity了。下面看该类代码:

package com.wzy.search.aty;

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

import com.wzy.search.R;
import com.wzy.search.bean.Person;
import com.wzy.search.util.HttpUtil;
import com.wzy.search.util.Material;
import com.wzy.search.util.SerializableMap;
import com.wzy.search.StringUtil;
import com.wzy.bean.PersonData;
import com.wzy.bean.StringBean;

import android.app.ActionBar;
import android.app.Activity;
import android.app.SearchManager;
import android.content.Intent;
import android.os.Bundle;
import android.os.DropBoxManager.Entry;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.Toast;
import android.widget.AdapterView.OnItemClickListener;

/**
 * 该类返回搜索的结果,并以表格的形式显示
 * @author wzy
 *
 */
public class SearchResultActvity extends Activity{

    private List<PersonData> datas;
    private ListView listView = null;

    private List<Map<String, String>> personDatas = null;
    private SimpleAdapter simpleAdapter = null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);

        setContentView(R.layout.result_names_new);

        ActionBar actionBar = getActionBar();
        actionBar.setDisplayHomeAsUpEnabled(true);// 给左上角图标左边加上一个返回图标
        actionBar.setDisplayShowHomeEnabled(true);// 设置ActionBar程序图标不可见

        listView = (ListView) findViewById(R.id.personList); // 获取Listview的引用

        personDatas = new ArrayList<Map<String, String>>();

        doSearchQuery(getIntent());

        // 将获取到的名称包装为SimpleAdapter
        simpleAdapter = new SimpleAdapter(SearchResultActvity.this, personDatas, R.layout.nameitems,
                new String[] { PersonData.NAME , PersonData.AGE, PersonData.ADDRESS },
                new int[] { R.id.tv_name, R.id.tv_age, R.id.tv_address });

        // 为ListView设置Adapter
        listView.setAdapter(simpleAdapter);
        // 为ListView的列表项的单击事件绑定事件监听器
        listView.setOnItemClickListener(new OnItemClickListener() {
            // 这里可以自己写点击事件
            }
        });
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.menu, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
        case android.R.id.home:
            finish();
            break;

        default:
            break;
        }
        return super.onOptionsItemSelected(item);
    }

    /**
     *  activity重新置顶
     */
    @Override
    protected void onNewIntent(Intent intent) {
        // TODO Auto-generated method stub
        doSearchQuery(intent);
    }

    /**
     * 对searchable activity的调用仍是标准的intent,我们可以从intent中获取信息,即要搜索的内容
     * @param intent
     */
    private void doSearchQuery(Intent intent){  
        if(intent == null) 
            return; 

        String queryAction = intent.getAction(); 
        if( Intent.ACTION_SEARCH.equals( intent.getAction())){  //如果是通过ACTION_SEARCH来调用,即如果通过搜索调用 
            String queryString = intent.getStringExtra(SearchManager.QUERY); //获取搜索内容
            Log.e("yep", queryString);

            datas = null;           
            final Map<String, String> params = new HashMap<String, String>();
            params.put(StringBean.NAME, queryString);

            new Thread(new Runnable() {
                @Override
                public void run() {

                    String encode = "utf-8";
                    try {
                        datas = HttpUtil.sendHttpRequst(params, encode);
                        if (datas == null) {
                            Log.e("connect result", "返回结果异常");
                        }else {
                            for (PersonData data : datas) {
                                System.out.println(data.getAge() + " " + data.getName() + " " + data.getAddress());
                                Map<String, String> newData = new HashMap<String, String>();
                                newData.put(PersonData.NAME, data.getName());
                                newData.put(PersonData.AGE, data.getAge());
                                newData.put(PersonData.ADDRESS, data.getAddress());
                                personDatas.add(newData);
                            }

                            for (Map<String, String> map : personDatas) {
                                for (Map.Entry<String, String> entry : map.entrySet()) {
                                    System.out.println(entry.getKey() + " --> " + entry.getValue());
                                }
                            }

                        }
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }

            }).start();

        }  

    }  
}

result_names_new.xml如下所示:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#ffffcc" >

    <FrameLayout
        android:id="@+id/id_fl"
        android:layout_width="match_parent"
        android:layout_height="20dip"
        android:layout_marginTop="10dip" >

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/search_for_details"
            android:textSize="16sp"
            android:textStyle="bold" />
    </FrameLayout>

    <LinearLayout
        android:id="@+id/id_ll"

        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/id_fl"
        android:layout_marginLeft="10dip"
        android:layout_marginRight="10dip"
        android:layout_marginTop="30dip"
        android:orientation="horizontal" >

        <TextView
            android:layout_width="0dip"
            android:layout_height="40dip"
            android:layout_marginRight="-1dp"
            android:layout_weight="1.3"
            android:singleLine="true"
            android:ellipsize="end"
            android:background="@drawable/textview_border"
            android:gravity="center"
            android:text="name"
            android:textSize="13sp" />

        <TextView
            android:layout_width="0dip"
            android:layout_height="40dip"
            android:layout_marginRight="-1dp"
            android:layout_weight="1"
            android:singleLine="true"
            android:ellipsize="end"
            android:background="@drawable/textview_border"
            android:gravity="center"
            android:text="age"
            android:textSize="13sp" />

        <TextView
            android:layout_width="0dip"
            android:layout_height="40dip"
            android:layout_weight="1"
            android:singleLine="true"
            android:ellipsize="end"
            android:background="@drawable/textview_border"
            android:gravity="center"
            android:text="address"
            android:textSize="13sp" />
    </LinearLayout>

    <ListView
        android:id="@+id/personList"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@id/id_ll"
        android:layout_alignRight="@id/id_ll"
        android:layout_below="@id/id_ll"
        android:layout_marginTop="1dp"
        android:headerDividersEnabled="false" >
    </ListView>

</RelativeLayout>

nameitems如下所示:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#ffffcc"
    android:orientation="horizontal" >

    <TextView
        android:id="@+id/tv_name"
        android:layout_width="0dip"
        android:layout_height="40dip"
        android:layout_marginRight="-1dp"
        android:layout_marginTop="-2dp"
        android:layout_weight="1.3"
        android:singleLine="true"
        android:ellipsize="end"
        android:background="@drawable/textview_border"
        android:clickable="true"
        android:gravity="center"
        android:textSize="13sp" />

    <TextView
        android:id="@+id/tv_age"
        android:layout_width="0dip"
        android:layout_height="40dip"
        android:layout_marginRight="-1dp"
        android:layout_marginTop="-2dp"
        android:layout_weight="1"
        android:singleLine="true"
        android:ellipsize="end"
        android:background="@drawable/textview_border"
        android:clickable="true"
        android:gravity="center"
        android:textSize="13sp" />

    <TextView
        android:id="@+id/tv_address"
        android:layout_width="0dip"
        android:layout_height="40dip"
        android:layout_marginTop="-2dp"
        android:layout_weight="1"
        android:singleLine="true"
        android:ellipsize="end"
        android:background="@drawable/textview_border"
        android:clickable="true"
        android:gravity="center"
        android:textSize="13sp" />

</LinearLayout>

从xml可以看出来,表格是自己画的,先是画出表头,然后再用ListView,再将list化成和表头一样的框,就成了表格了。只不过需要调整一下间距,否则比较难看。
这里还有几个点:
一是调用HttpUtil方法时,必须使用线程,否则会报错;
二是对于listview的操作,比如初始化和setAdapter,必须放在onCreate方法里,否则会出现问题。

通信

本例使用HttpUrlConnection进行通信,在com.wzy.util包下新建HttpUtil类,主要用于发送前台传到后台的参数,并且接受后台传过来的数据,并且把数据包装成PersonData的形式。

package com.wzy.util;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
i   mport java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;

import com.google.gson.Gson;
import com.google.gson.reflect.TypeToken;
import com.siemens.bean.MaterialData;

import android.util.Log;

/**
 * 该类用于与后台进行通信,通过json方式,将结果以PersonData形式进行封装
 * @author wzy
 *
 */
public class HttpUtil {

    private final static String PATH = "http://127.0.0.1:8088/PersonServlet/QueryController";
    private static URL url;

    private static List<PersonData> datas = null;

    public HttpUtil() {

    }

    @SuppressWarnings("deprecation")
    public static List<PersonData> sendHttpRequst(Map<String, String> params, String encode) throws Exception {

        datas = new ArrayList<PersonData>();

        // 对查询的参数进行封装
        StringBuffer buffer = new StringBuffer();
        if (params != null && !params.isEmpty()) {
            for (Map.Entry<String, String> entry : params.entrySet()) {
                buffer.append(entry.getKey()).append("=").append(URLEncoder.encode(entry.getValue())).append("&");
            }
            buffer.deleteCharAt(buffer.length() - 1);
        }

        // 打印传递的参数
        Log.e("data", buffer.toString());

        try {
            url = new URL(PATH);
//          System.out.println("url:" + url.toString());
            if (url != null) {
                HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
                Log.e("TEST", urlConnection+"");
                if (urlConnection == null) {
                    System.out.println("urlConnection: " + urlConnection);
                    return null;
                }
                urlConnection.setConnectTimeout(3000);
                urlConnection.setRequestMethod("POST"); // 设置请求方式
                urlConnection.setDoInput(true); // 表示从服务器获取数据
                urlConnection.setDoOutput(true); // 表示向服务器发送数据
                byte[] data = buffer.toString().getBytes();

//              System.out.println("buffer:" + data.toString());

                // 设置请求体的是文本类型
                urlConnection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
                urlConnection.setRequestProperty("Content-Length", String.valueOf(data.length));

                // 获得输出流
                OutputStream outputStream = urlConnection.getOutputStream();
                outputStream.write(data);
                outputStream.close();

                // 获得服务器的响应结果和状态码
                int responseCode = urlConnection.getResponseCode();
                Log.e("RESCODE", responseCode + "");
                // 服务器响应成功
                if (responseCode == 200) {
                    // 获取查询结果
                    InputStream in = urlConnection.getInputStream();

                    // 结果为JSON格式,对JSON进行解析
                    datas = parseJSON(in);
                }
            }
            return datas;
        } catch (IOException e) {
            e.printStackTrace();
            Log.e("my error", "这里肯定发生了错误");
        }
        return null;
    }

    private static List<PersonData> parseJSON(InputStream in) throws Exception {

        String str = read(in);

        Gson gson = new Gson();
        datas = gson.fromJson(str, new TypeToken<List<PersonData>>(){}.getType());
        return datas;
    }

    private static String read(InputStream in) throws IOException {
        byte[] data;
        ByteArrayOutputStream bout = new ByteArrayOutputStream();
        byte[] buf = new byte[1024];
        int len = 0;
        while ((len = in.read(buf)) != -1) {
            bout.write(buf, 0, len);
        }
        data = bout.toByteArray();
        return new String(data, "utf-8");
    }

}

这里就没什么好说的了,需要注意的是,这里用Gson进行的数据解析,讲json转化为PeronData,传给SearchResultActivity

后台

后台代码结构

本例中,后台不需要view层,所以只需要以下包
-com.wzy.bean,封装数据库的表;
-com.wzy.service,对某个表进行操作;
-com.wzy.controller,控制某个service进行操作;
-com.wzy.util,有SqlHelper类,进行数据库的增删改查操作,涉及数据库的都可以用这个类,也可以叫com.wzy.dao包;
本例中,用QueryController接受前台传过来的数据,并用PersonService进行查询操作,返回PersonData数据

QueryController

代码如下:

package com.wzy.controller;

import java.io.IOException;
import java.io.OutputStream;
import java.util.ArrayList;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.google.gson.Gson;
import com.wzy.bean.PersonData;
import com.wzy.bean.StringBean;
import com.wzy.service.PersonService;

/**
 * 该类用于控制查询相关事务,不包括单表查询。即需要查询多个表,通过该controller,调用相关service进行处理
 * @author wzy
 *
 */
public class QueryController extends HttpServlet {
    private static final long serialVersionUID = 1L;

    private String materialName = "";

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        doPost(request, response);
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub

        request.setCharacterEncoding("utf-8");
        response.setContentType("text/json;charset=utf-8");
        response.setContentType("utf-8");

        OutputStream out = response.getOutputStream();

        ArrayList<PersonData> datas = null; //定义需要返回的数据

        if (request != null) {
            name = request.getParameter(StringBean.NAME);

            // 调用PersonService的方法,根据名字得到需要返回的ArrayList
            PersonService personService = new PersonService();
            datas = personService.getPersonByName(name);

            // 测试代码,输出查询到的数据
            for (PersonData data : datas) {
                System.out.println(data);
            }

            // 通过gson返回数据
            Gson gson = new Gson();
            out.write(gson.toJson(datas).getBytes("utf-8"));

            out.flush();
            out.close();
        }

    }

}

需要注意的是,要用json的话,需要导包,这个可以百度一下,有一个主要包,还有几个支持包,都要导

MaterialService类

package com.wzy.service;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.HashMap;

import com.google.gson.Gson;
import com.wzy.bean.PersonData;
import com.wzy.bean.Person_name;
import com.wzy.utils.DBString;
import com.wzy.utils.SqlHelper;

/**
 * 对涉及多表的业务进行操作
 * @author wzy
 *
 */
public class PersonService {

    private String sql = "";
    private String[] params = null;
    private PersonData data = null;
    private ArrayList<PersonData> datas = null;

    /**
     * 根据name查找,并返回封装name,age,address的数据结构
     * @param name
     * @return 封装name,age,address的对象的ArrayList
     */
    public ArrayList<PersonData> getPersonByName (String name) {


        params = new String[]{"%" + name + "%"};

        sql = "select "+Person_name.NAME+","+Person_name.AGE+","
                +Person_name.ADDRESS+" from "+DBString.TABLE_Person_NAME
                +" where "+Person_name.PERSON_NAME+" like ?";
        System.out.println("sql test:" + sql);

        ResultSet rs = SqlHelper.executeQuery(sql,params);

        datas = new ArrayList<>();

        try {
            while (rs.next()) {
                data = new PersonData();
                data.setPersonAge(rs.getString(Person_name.PERSON_AGE));
                data.setPersonName(rs.getString(Person_name.PERSON_NAME));
                data.setPersonAddress(rs.getString(Person_name.ADDRESS));
                datas.add(data);
            }
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } finally {
            SqlHelper.close(SqlHelper.getConn(), SqlHelper.getStat(), rs);
        }

        return datas;
    }

}

这里又有一个坑:
当preparestatement语句中,有?又有%时,需要把%放在params定义中,而不能够放在?旁边,这个错误检查了半天,始终找不出来,最后还是慢慢试出来的。
另外,上面代码提到的Person_name是一个表,里面仅仅存放了所有人的名字,方便用于查找用的。

说明

上面的代码仅供参考,留待以后使用,有一些代码没有贴出来。

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