C3P0連接配接Mysql8.0.11的配置問題
小白一個,這幾天,在學C3P0資料連接配接池,把遇到的一些問題記錄一下,希望能幫到你們。
題主的環境:
- Eclipse
- C3P0-0.9.5.2 可參考這裡下載下傳
- Mysql8.0.11
Eclipse目錄結構如下:
1.建立配置檔案c3p0-config.xml
在src(類路徑)目錄下添加配置檔案c3p0-config.xml
<?xml version="1.0" encoding="UTF-8" ?>
<c3p0-config>
//預設的配置
<default-config>
<property name="jdbcUrl">jdbc:mysql://localhost:3306/mydb_02?&useSSL=false&serverTimezone=UTC</property>
<propertyname="driverClass">com.mysql.cj.jdbc.Driver</property>
<property name="user">root</property>
<property name="password">123456</property?
<property name="acquireIncrement">3</property>
<property name="initialPoolSize">10</property>
<property name="minPoolSize">2</property>
<property name="maxPoolSize">10</property>
<named-config name="oracle">
</default-config>
</c3p0-config>
請注意,這個配置檔案可能會出現的錯誤如下:
-
[ 1]對實體‘useSSL’ 的引用必須以 ‘;’ 分隔符結尾.
-
解決辦法:在jdbcUrl中所有帶 ‘&’的後面加上amp并加上;
如:
jdbc:mysql://localhost:3306/資料庫名?&useSSL=false&serverTimezone=UTC
- [2 ] not Suitable driver
解決辦法:JDBC版本和C3P0版本不相容,題主開始用的mysql8.0.11+c3p0-0.9.1.2報了這個異常,後來去下了c3p0最新版(0.9.5.2)得以解決。
2.工具類C3P0Utils
package cn.lds.C3P0;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.sql.DataSource;
import com.mchange.v2.c3p0.ComboPooledDataSource;
public class C3P0Utils {
private static ComboPooledDataSource dataSource = new ComboPooledDataSource();
//獲得資料源
public static DataSource getDataSource() {
return dataSource;
}
//獲得連接配接對象
public static Connection getConnection() {
try {
return dataSource.getConnection();
} catch (SQLException e) {
throw new RuntimeException(e);
}
}
//釋放資源
public static void release(Connection con, PreparedStatement par, ResultSet re) {
if (re != null) {
try {
re.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (par != null) {
try {
par.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (con != null) {
try {
con.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
3.測試類TestC3P0
package cn.lds.C3P0;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
public class TestC3P0 {public static void main(String[] args) {
TestAdd();
}
public static void TestAdd() {
Connection con =null;
PreparedStatement ps=null;
try {
con=C3P0Utils.getConnection();
String sql="insert into login_inf values(?,?)";
ps=con.prepareStatement(sql);
ps.setString(1, "張飛");
ps.setString(2, "123456");
int row = ps.executeUpdate();
if(row>0) {
System.out.println("插入成功");
}else {
System.out.println("插入失敗");
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
C3P0Utils.release(con, ps, null);
}
}
4.運作結果
想想自己也是夠笨的,折騰了3小時。。。。