最近学习了JDBC的相关知识，写一下自定义连接池
一些说明：
本代码参考了部分别人的代码！！！
JDBCCon类具体创建了连接；
MyConnection类集成了Connection类用来管理连接与池，其中的close方法必须pool.add()；
MyDataSource则是具体实现连接池。
具体步骤：
1、导mysql的jar包
2、配置db.propertites
1 driver = com.mysql.cj.jdbc.Driver 2 url = jdbc:mysql://localhost:3306/test?serverTimezone=GMT 3 username = root 4 password = root
3、JDBCCon
1 package com.nick.util;
2
3 import java.io.IOException;
4 import java.io.InputStream;
5 import java.sql.Connection;
6 import java.sql.DriverManager;
7 import java.sql.PreparedStatement;
8 import java.sql.ResultSet;
9 import java.sql.SQLException;
10 import java.util.Properties;
11
12 public class JDBCCon {
13
14 private static String driver;
15 private static String url;
16 private static String username;
17 private static String password;
18
19
20 static {
21
22 try {
23 ClassLoader classLoader = JDBCCon.class.getClassLoader();
24 InputStream is = classLoader.getResourceAsStream("db.properties");
25 Properties props = new Properties();
26 props.load(is);
27 driver = props.getProperty("driver");
28 url = props.getProperty("url");
29 username = props.getProperty("username");
30 password = props.getProperty("password");
31 } catch (IOException e) {
32 // TODO Auto-generated catch block
33 e.printStackTrace();
34 }
35
36 }
37
38 public static Connection getConnection() {
39 Connection connection = null;
40 try {
41 Class.forName(driver);
42 connection = DriverManager.getConnection(url, username, password);
43 } catch (Exception e) {
44 // TODO: handle exception
45 }
46 return connection;
47
48 }
49
50 public static void release(Connection conn, PreparedStatement pstmt, ResultSet rs) {
51 if(rs != null) {
52 try {
53 rs.close();
54 } catch (SQLException e) {
55 // TODO Auto-generated catch block
56 e.printStackTrace();
57 }
58 }
59 if(pstmt != null) {
60 try {
61 pstmt.close();
62 } catch (SQLException e) {
63 // TODO Auto-generated catch block
64 e.printStackTrace();
65 }
66 }
67 if(conn != null) {
68 try {
69 conn.close();
70 } catch (SQLException e) {
71 // TODO Auto-generated catch block
72 e.printStackTrace();
73 }
74 }
75
76 }
77
78 }
4、MyConnection
1 package com.nick.dataSource;
2
3 import java.sql.Array;
4 import java.sql.Blob;
5 import java.sql.CallableStatement;
6 import java.sql.Clob;
7 import java.sql.Connection;
8 import java.sql.DatabaseMetaData;
9 import java.sql.NClob;
10 import java.sql.PreparedStatement;
11 import java.sql.SQLClientInfoException;
12 import java.sql.SQLException;
13 import java.sql.SQLWarning;
14 import java.sql.SQLXML;
15 import java.sql.Savepoint;
16 import java.sql.Statement;
17 import java.sql.Struct;
18 import java.util.LinkedList;
19 import java.util.Map;
20 import java.util.Properties;
21 import java.util.concurrent.Executor;
22
23 public class MyConnection implements Connection{
24
25 private Connection connection = null;
26 private LinkedList<Connection> pool = null;
27 public MyConnection(Connection connection, LinkedList<Connection> pool) {
28 this.connection = connection;
29 this.pool = pool;
30 }
31
32 @Override
33 public void close() throws SQLException {
34 // TODO Auto-generated method stub
35 pool.add(connection);
36 }
37
38 @Override
39 public <T> T unwrap(Class<T> iface) throws SQLException {
40 // TODO Auto-generated method stub
41 return null;
42 }
43 @Override
44 public boolean isWrapperFor(Class<?> iface) throws SQLException {
45 // TODO Auto-generated method stub
46 return false;
47 }
48 @Override
49 public Statement createStatement() throws SQLException {
50 // TODO Auto-generated method stub
51 return null;
52 }
53 @Override
54 public PreparedStatement prepareStatement(String sql) throws SQLException {
55 // TODO Auto-generated method stub
56 return null;
57 }
58 @Override
59 public CallableStatement prepareCall(String sql) throws SQLException {
60 // TODO Auto-generated method stub
61 return null;
62 }
63 @Override
64 public String nativeSQL(String sql) throws SQLException {
65 // TODO Auto-generated method stub
66 return null;
67 }
68 @Override
69 public void setAutoCommit(boolean autoCommit) throws SQLException {
70 // TODO Auto-generated method stub
71
72 }
73 @Override
74 public boolean getAutoCommit() throws SQLException {
75 // TODO Auto-generated method stub
76 return false;
77 }
78 @Override
79 public void commit() throws SQLException {
80 // TODO Auto-generated method stub
81
82 }
83 @Override
84 public void rollback() throws SQLException {
85 // TODO Auto-generated method stub
86
87 }
88
89 @Override
90 public boolean isClosed() throws SQLException {
91 // TODO Auto-generated method stub
92 return false;
93 }
94 @Override
95 public DatabaseMetaData getMetaData() throws SQLException {
96 // TODO Auto-generated method stub
97 return null;
98 }
99 @Override
100 public void setReadOnly(boolean readOnly) throws SQLException {
101 // TODO Auto-generated method stub
102
103 }
104 @Override
105 public boolean isReadOnly() throws SQLException {
106 // TODO Auto-generated method stub
107 return false;
108 }
109 @Override
110 public void setCatalog(String catalog) throws SQLException {
111 // TODO Auto-generated method stub
112
113 }
114 @Override
115 public String getCatalog() throws SQLException {
116 // TODO Auto-generated method stub
117 return null;
118 }
119 @Override
120 public void setTransactionIsolation(int level) throws SQLException {
121 // TODO Auto-generated method stub
122
123 }
124 @Override
125 public int getTransactionIsolation() throws SQLException {
126 // TODO Auto-generated method stub
127 return 0;
128 }
129 @Override
130 public SQLWarning getWarnings() throws SQLException {
131 // TODO Auto-generated method stub
132 return null;
133 }
134 @Override
135 public void clearWarnings() throws SQLException {
136 // TODO Auto-generated method stub
137
138 }
139 @Override
140 public Statement createStatement(int resultSetType, int resultSetConcurrency) throws SQLException {
141 // TODO Auto-generated method stub
142 return null;
143 }
144 @Override
145 public PreparedStatement prepareStatement(String sql, int resultSetType, int resultSetConcurrency)
146 throws SQLException {
147 // TODO Auto-generated method stub
148 return null;
149 }
150 @Override
151 public CallableStatement prepareCall(String sql, int resultSetType, int resultSetConcurrency) throws SQLException {
152 // TODO Auto-generated method stub
153 return null;
154 }
155 @Override
156 public Map<String, Class<?>> getTypeMap() throws SQLException {
157 // TODO Auto-generated method stub
158 return null;
159 }
160 @Override
161 public void setTypeMap(Map<String, Class<?>> map) throws SQLException {
162 // TODO Auto-generated method stub
163
164 }
165 @Override
166 public void setHoldability(int holdability) throws SQLException {
167 // TODO Auto-generated method stub
168
169 }
170 @Override
171 public int getHoldability() throws SQLException {
172 // TODO Auto-generated method stub
173 return 0;
174 }
175 @Override
176 public Savepoint setSavepoint() throws SQLException {
177 // TODO Auto-generated method stub
178 return null;
179 }
180 @Override
181 public Savepoint setSavepoint(String name) throws SQLException {
182 // TODO Auto-generated method stub
183 return null;
184 }
185 @Override
186 public void rollback(Savepoint savepoint) throws SQLException {
187 // TODO Auto-generated method stub
188
189 }
190 @Override
191 public void releaseSavepoint(Savepoint savepoint) throws SQLException {
192 // TODO Auto-generated method stub
193
194 }
195 @Override
196 public Statement createStatement(int resultSetType, int resultSetConcurrency, int resultSetHoldability)
197 throws SQLException {
198 // TODO Auto-generated method stub
199 return null;
200 }
201 @Override
202 public PreparedStatement prepareStatement(String sql, int resultSetType, int resultSetConcurrency,
203 int resultSetHoldability) throws SQLException {
204 // TODO Auto-generated method stub
205 return null;
206 }
207 @Override
208 public CallableStatement prepareCall(String sql, int resultSetType, int resultSetConcurrency,
209 int resultSetHoldability) throws SQLException {
210 // TODO Auto-generated method stub
211 return null;
212 }
213 @Override
214 public PreparedStatement prepareStatement(String sql, int autoGeneratedKeys) throws SQLException {
215 // TODO Auto-generated method stub
216 return null;
217 }
218 @Override
219 public PreparedStatement prepareStatement(String sql, int[] columnIndexes) throws SQLException {
220 // TODO Auto-generated method stub
221 return null;
222 }
223 @Override
224 public PreparedStatement prepareStatement(String sql, String[] columnNames) throws SQLException {
225 // TODO Auto-generated method stub
226 return null;
227 }
228 @Override
229 public Clob createClob() throws SQLException {
230 // TODO Auto-generated method stub
231 return null;
232 }
233 @Override
234 public Blob createBlob() throws SQLException {
235 // TODO Auto-generated method stub
236 return null;
237 }
238 @Override
239 public NClob createNClob() throws SQLException {
240 // TODO Auto-generated method stub
241 return null;
242 }
243 @Override
244 public SQLXML createSQLXML() throws SQLException {
245 // TODO Auto-generated method stub
246 return null;
247 }
248 @Override
249 public boolean isValid(int timeout) throws SQLException {
250 // TODO Auto-generated method stub
251 return false;
252 }
253 @Override
254 public void setClientInfo(String name, String value) throws SQLClientInfoException {
255 // TODO Auto-generated method stub
256
257 }
258 @Override
259 public void setClientInfo(Properties properties) throws SQLClientInfoException {
260 // TODO Auto-generated method stub
261
262 }
263 @Override
264 public String getClientInfo(String name) throws SQLException {
265 // TODO Auto-generated method stub
266 return null;
267 }
268 @Override
269 public Properties getClientInfo() throws SQLException {
270 // TODO Auto-generated method stub
271 return null;
272 }
273 @Override
274 public Array createArrayOf(String typeName, Object[] elements) throws SQLException {
275 // TODO Auto-generated method stub
276 return null;
277 }
278 @Override
279 public Struct createStruct(String typeName, Object[] attributes) throws SQLException {
280 // TODO Auto-generated method stub
281 return null;
282 }
283 @Override
284 public void setSchema(String schema) throws SQLException {
285 // TODO Auto-generated method stub
286
287 }
288 @Override
289 public String getSchema() throws SQLException {
290 // TODO Auto-generated method stub
291 return null;
292 }
293 @Override
294 public void abort(Executor executor) throws SQLException {
295 // TODO Auto-generated method stub
296
297 }
298 @Override
299 public void setNetworkTimeout(Executor executor, int milliseconds) throws SQLException {
300 // TODO Auto-generated method stub
301
302 }
303 @Override
304 public int getNetworkTimeout() throws SQLException {
305 // TODO Auto-generated method stub
306 return 0;
307 }
308 }
5、MyDataSource
1 package com.nick.dataSource;
2
3 import java.sql.Connection;
4 import java.util.LinkedList;
5
6 import com.nick.util.JDBCCon;
7
8 public class MyDataSource {
9
10 private static LinkedList<Connection> pool = new LinkedList<Connection>();
11
12 static {
13 //
14 for(int i = 0; i < 5; i++) {
15 Connection connection = JDBCCon.getConnection();
16 pool.add(connection);
17 }
18 }
19
20 public static Connection getConnection() {
21 if(pool.size() == 0) {
22 for(int i = 0; i < 5; i++) {
23 Connection connection = JDBCCon.getConnection();
24 MyConnection myConnection = new MyConnection(connection, pool);
25 pool.add(myConnection);
26 }
27 }
28 Connection connection = pool.remove(0);
29 return connection;
30
31 }
32 }
6、检测代码
1 package com.nick.test;
2
3 import java.sql.Connection;
4 import java.sql.PreparedStatement;
5
6 import org.junit.jupiter.api.Test;
7
8 import com.nick.dataSource.MyDataSource;
9 import com.nick.util.JDBCCon;
10
11 public class TestDemo01 {
12
13 @Test
14 public void t1() {
15 Connection connection = null;
16 PreparedStatement pstmt = null;
17 MyDataSource myDataSource = new MyDataSource();
18 try {
19 connection = myDataSource.getConnection();
20 String sql = "insert into student values (?,?,?,?)";
21 PreparedStatement prepareStatement = connection.prepareStatement(sql);
22 prepareStatement.setInt(1, 10);
23 prepareStatement.setString(2, "吕布");
24 prepareStatement.setString(3, "男");
25 prepareStatement.setInt(4, 100);
26 int rows = prepareStatement.executeUpdate();
27 if(rows > 0) {
28 System.out.println("OK");
29 }else {
30 System.out.println("NO");
31 }
32 } catch (Exception e) {
33 // TODO: handle exception
34 }
35 }
36 }
以上即全部代码。
原文地址：https://www.cnblogs.com/nick9527/p/9873976.html
时间： 2024-10-09 05:08:24