在安卓环境下连接数据库下面是主要代码极其作用：
1.编写 The Class类把课程表courses.db当做一个实体类，hashcode和equals这两个类是为了判断输入的查询内容和Excel表中的内容是否一致。
并在java里面区别两个对象是否一致
1 public class TheClass {2 private String classname;3 private String type;4 private String teacher;5 private String classroom;6 public String getClassname() {7 return classname;8 }9 public void setClassname(String classname) {
10 this.classname = classname;
11 }
12 public String getType() {
13 return type;
14 }
15 public void setType(String type) {
16 this.type = type;
17 }
18 public String getTeacher() {
19 return teacher;
20 }
21 public void setTeacher(String teacher) {
22 this.teacher = teacher;
23 }
24 public String getClassroom() {
25 return classroom;
26 }
27 public void setClassroom(String classroom) {
28 this.classroom = classroom;
29 }
30 @Override
31 public int hashCode() {
32 final int prime = 31;
33 int result = 1;
34 result = prime * result
35 + ((classname == null) ? 0 : classname.hashCode());
36 result = prime * result
37 + ((classroom == null) ? 0 : classroom.hashCode());
38 result = prime * result + ((teacher == null) ? 0 : teacher.hashCode());
39 result = prime * result + ((type == null) ? 0 : type.hashCode());
40 return result;
41 }
42 @Override
43 public boolean equals(Object obj) {
44 if (this == obj)
45 return true;
46 if (obj == null)
47 return false;
48 if (getClass() != obj.getClass())
49 return false;
50 TheClass other = (TheClass) obj;
51 if (classname == null) {
52 if (other.classname != null)
53 return false;
54 } else if (!classname.equals(other.classname))
55 return false;
56 if (classroom == null) {
57 if (other.classroom != null)
58 return false;
59 } else if (!classroom.equals(other.classroom))
60 return false;
61 if (teacher == null) {
62 if (other.teacher != null)
63 return false;
64 } else if (!teacher.equals(other.teacher))
65 return false;
66 if (type == null) {
67 if (other.type != null)
68 return false;
69 } else if (!type.equals(other.type))
70 return false;
71 return true;
72 }
73
74 }这里必须注意的是hashset是个集合，必须两者是不同的，那么怎么进行区分呢，就是通过hashcode和equals这两个类
2.编写Readfile类，导入Excle的类进入sqlite
1 public class ReadFile {2 3 public static boolean read2DB(File f, Context con) {4 try {5 Workbook course = null;6 course = Workbook.getWorkbook(f);7 Sheet sheet = course.getSheet(0);8 HashSet<TheClass> subjects = new HashSet<TheClass>();9 Cell cell = null;
10 for (int i = 1; i < sheet.getRows(); i++) {
11 TheClass tc = new TheClass();
12 cell = sheet.getCell(2, i);
13 tc.setClassname(cell.getContents());
14 cell = sheet.getCell(10, i);
15 tc.setType(cell.getContents());
16 cell = sheet.getCell(12, i);
17 tc.setTeacher(cell.getContents());
18 cell = sheet.getCell(18, i);
19 tc.setClassroom(cell.getContents());
20 System.out.println(tc.getClassname() + tc.getType()
21 + tc.getTeacher() + tc.getClassroom());
22 subjects.add(tc);
23 }
24 SQLiteDatabase db = new SQLiteHelper(con, "courses.db")
25 .getWritableDatabase();
26 for (TheClass tc : subjects) {
27 ContentValues cv = new ContentValues();
28 cv.put("classname", tc.getClassname());
29 cv.put("type", tc.getType());
30 cv.put("teacher", tc.getTeacher());
31 cv.put("classroom", tc.getClassroom());
32 db.insert("table1", null, cv);
33 }
34 return true;
35 } catch (Exception e) {
36 // TODO Auto-generated catch block
37 e.printStackTrace();
38 return false;
39 }
40 }
41 }3.编写sqlite帮助类，通过它可以比较快的创建数据对象，创建表，删除表
1 public class SQLiteHelper extends SQLiteOpenHelper {2 3 public SQLiteHelper(Context context, String name, CursorFactory factory,4 int version) {5 super(context, name, factory, version);6 }7 public SQLiteHelper(Context con, String name){8 this(con, name, null, 1);9 }
10
11 @Override
12 public void onCreate(SQLiteDatabase db) {
13 // TODO Auto-generated method stub
14 db.execSQL("create table table1(classname varchar(20), type varchar(10), teacher varchar(20), classroom varchar(20))");
15 }
16
17 @Override
18 public void onUpgrade(SQLiteDatabase db, int oldv, int newv) {
19 // TODO Auto-generated method stub
20 db.execSQL("drop table if exists table1");
21 onCreate(db);
22 }
23
24 }4.编写主函数MainActivity，添加查询课程，老师，修改教室，老师等点击事件，还有刚开始加载Excel表的数据
1 public class MainActivity extends Activity {2 3 private TextView hello;4 private Button b1;5 private EditText et;6 // private Spinner sp;7 private EditText et2;8 private SQLiteDatabase db = null;9 private TextView type;10 private TextView classroom;11 private Button editclassroom;12 private Button del;13 private String classname;14 private String teachername;15 private EditText edclassroom;16 17 @Override18 protected void onCreate(Bundle savedInstanceState) {19 super.onCreate(savedInstanceState);20 setContentView(R.layout.activity_main);21 db = new SQLiteHelper(this, "courses.db").getWritableDatabase();22 hello = (TextView) findViewById(R.id.hello);23 b1 = (Button) findViewById(R.id.button1);24 b1.setOnClickListener(new View.OnClickListener() {25 26 @Override27 public void onClick(View arg0) {28 LayoutInflater li = LayoutInflater.from(MainActivity.this);29 View view = li.inflate(R.layout.quer, null);30 et = (EditText) view.findViewById(R.id.editText1);31 // sp = (Spinner) findViewById(R.id.spinner1);32 et2 = (EditText) view.findViewById(R.id.EditText01);33 new AlertDialog.Builder(MainActivity.this)34 .setTitle("查询")35 .setView(view)36 .setPositiveButton("确定",37 new DialogInterface.OnClickListener() {38 39 @Override40 public void onClick(DialogInterface arg0,41 int arg1) {42 classname = et.getText().toString();43 teachername = et2.getText().toString();44 if (null != classname45 && null != teachername) {46 Cursor c = db47 .rawQuery(48 "select type,classroom from table1 where classname = ? and teacher = ? ",49 new String[] {50 classname,51 teachername });52 LayoutInflater li = LayoutInflater53 .from(MainActivity.this);54 View view = li.inflate(55 R.layout.show, null);56 type = (TextView) view57 .findViewById(R.id.type);58 classroom = (TextView) view59 .findViewById(R.id.classroom);60 editclassroom = (Button) view61 .findViewById(R.id.button1);62 del = (Button) view63 .findViewById(R.id.button2);64 c.moveToNext();65 type.setText(c.getString(c66 .getColumnIndex("type")));67 classroom.setText(c.getString(c68 .getColumnIndex("classroom")));69 70 new AlertDialog.Builder(71 MainActivity.this)72 .setTitle("查询结果")73 .setView(view)74 .setPositiveButton("确定",75 null).show();76 editclassroom77 .setOnClickListener(new View.OnClickListener() {78 79 @Override80 public void onClick(81 View arg0) {82 LayoutInflater li = LayoutInflater83 .from(MainActivity.this);84 View editview = li85 .inflate(86 R.layout.editclassroom,87 null);88 edclassroom = (EditText) editview89 .findViewById(R.id.editText1);90 new AlertDialog.Builder(91 MainActivity.this)92 .setTitle(93 "新的教室：")94 .setView(95 editview)96 .setPositiveButton(97 "确定",98 new DialogInterface.OnClickListener() {99
100 @Override
101 public void onClick(DialogInterface arg0, int arg1) {
102 ContentValues cv = new ContentValues();
103 cv.put("classroom", edclassroom.getText().toString());
104 db.update("table1", cv, "classname = ? and teacher = ?",
105 new String[] {
106 classname,
107 teachername });
108 }
109 })
110 .setNegativeButton(
111 "取消",
112 null)
113 .show();
114 }
115 });
116
117 del.setOnClickListener(new View.OnClickListener() {
118
119 @Override
120 public void onClick(View arg0) {
121 new AlertDialog.Builder(
122 MainActivity.this)
123 .setTitle("警告")
124 .setMessage(
125 "您正在删除记录，确定删除？")
126 .setPositiveButton(
127 "确定",
128 new DialogInterface.OnClickListener() {
129
130 @Override
131 public void onClick(
132 DialogInterface arg0,
133 int arg1) {
134 db.delete(
135 "table1",
136 "classname = ? and teacher = ?",
137 new String[] {
138 classname,
139 teachername });
140 }
141 })
142 .setNegativeButton(
143 "取消", null)
144 .show();
145 }
146 });
147
148 }
149 }
150
151 }).show();
152 }
153 });
154 File sdpath = Environment.getExternalStorageDirectory();
155 File coursefile = new File(sdpath + File.separator + "courses.xls");
156 if (!coursefile.exists()) {
157 new AlertDialog.Builder(this).setTitle("错误").setMessage("未找到文件")
158 .setPositiveButton("确定", null).show();
159 b1.setVisibility(View.INVISIBLE);
160 } else {
161 hello.setText("找到了文件！");
162 new Important().execute();
163 b1.setVisibility(View.VISIBLE);
164 }
165 }
166
167 @Override
168 public boolean onCreateOptionsMenu(Menu menu) {
169 // Inflate the menu; this adds items to the action bar if it is present.
170 getMenuInflater().inflate(R.menu.main, menu);
171 return true;
172 }
173
174 class Important extends AsyncTask<Integer, String, Boolean> {
175 private ProgressDialog pDialog = null;
176
177 @Override
178 protected void onPreExecute() {
179 // TODO Auto-generated method stub
180 super.onPreExecute();
181 pDialog = new ProgressDialog(MainActivity.this);
182 pDialog.setMessage("正在导入课程，请稍候");
183 pDialog.setIndeterminate(false);
184 pDialog.setCancelable(true);
185 pDialog.show();
186 }
187
188 @Override
189 protected void onPostExecute(Boolean imp) {
190 // TODO Auto-generated method stub
191 super.onPostExecute(imp);
192 pDialog.dismiss();
193 String result = "";
194 if (imp == true) {
195 result = "读取成功!";
196 } else {
197 result = "读取失败！";
198 }
199 new AlertDialog.Builder(MainActivity.this).setTitle("提示")
200 .setMessage(result).setPositiveButton("确定", null).show();
201
202 }
203
204 @Override
205 protected void onProgressUpdate(String... values) {
206 // TODO Auto-generated method stub
207 super.onProgressUpdate(values);
208 }
209
210 @Override
211 protected Boolean doInBackground(Integer... params) {
212 File sdpath = Environment.getExternalStorageDirectory();
213 File coursefile = new File(sdpath + File.separator + "courses.xls");
214 return ReadFile.read2DB(coursefile, MainActivity.this);
215 }
216 }
217
218 }5.整个过程不是太难，不过要记得导入jxl.jar这个包，整体技术方面就是用到了安卓本身自带的Sqlite操作方法，还要注意必须把excel表导入虚拟器或实体机的id卡中，因为实在安卓环境下运行，所以一定会用到虚拟器或实体机，只有把excel导入id卡后我们才能用这个程序进行增删改查的操作。
