Java JDBC连接各种数据库实例
在本文章中，我们来学习Java中不同类型数据库的JDBC驱动程序库的使用。
1- 介绍
下面文章将介绍下载和使用一些数据库的JDBC驱动程序库。在这里，有关数据库类型如下：
- Oracle
- MySQL
- SQL Server.
2- 对于Oracle的JDBC驱动程序
Oracle数据库库驱动程序通常命名为：ojdbc14.jar, ojdbc6.jar, ... 所不同的是它打包的Java版本。- ojdbc14.jar: 由Java1.4版编译和打包
- ojdbc6.jar: 由Java1.6版编译和打包
更多详细信息可以查看并从甲骨文网站下载：
- http://www.oracle.com/technetwork/database/enterprise-edition/jdbc-112010-090769.html
要从甲骨文网站下载文件，必须有一个Oracle帐号(免费注册)。
为了节省时间，您可以通过以下链接下载：
- https://code.google.com/p/afirs/downloads/detail?name=ojdbc6.jar
下载结果：
2.1- Maven关联Oracle JDBC驱动程序
....... codelds https://code.lds.org/nexus/content/groups/main-repo ...... ....... com.oracle ojdbc6 11.2.0.3
2.2- 如何使用 (ojdbc)？
// Driver class: oracle.jdbc.driver.OracleDriver // URL Connection String: (SID) String urlString ="jdbc:oracle:thin:@myhost:1521:mysid" // URL Connection String: (Service Name) String urlString ="jdbc:oracle:thin:username/pass@//myhost:1521/myservicename" // Or: String urlString ="jdbc:oracle:thin:@myhost:1521/myservicename";
例如 JDBC 连接到 Oracle 数据库。
- OracleConnUtils.java
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class OracleConnUtils {
public static Connection getOracleConnection()
throws ClassNotFoundException, SQLException {
String hostName = "localhost";
String sid = "db11g";
String userName = "learningsql";
String password = "1234";
return getOracleConnection(hostName, sid, userName, password);
}
public static Connection getOracleConnection(String hostName, String sid,
String userName, String password) throws ClassNotFoundException,
SQLException {
// Declare the class Driver for Oracle DB
// This is necessary with Java 5 (or older)
// Java6 (or newer) automatically find the appropriate driver.
// If you use Java> 6, then this line is not needed.
Class.forName("oracle.jdbc.driver.OracleDriver");
// Example: jdbc:oracle:thin:@localhost:1521:db11g
String connectionURL = "jdbc:oracle:thin:@" + hostName + ":1521:" + sid;
Connection conn = DriverManager.getConnection(connectionURL, userName,
password);
return conn;
}
}
3- MySQL的JDBC驱动程序
也可以下载MySQL数据库JDBC库在：
- http://mvnrepository.com/artifact/mysql/mysql-connector-java
下载结果：
3.1- 如何使用？
如何使用MySQL-connector-java-xxx.jar : (JDBC for MySQL)
// Driver class: com.mysql.jdbc.Driver // URL Connection String: String url = "jdbc:mysql://hostname:3306/dbname"; // Example: String url = "jdbc:mysql://localhost:3306/simplehr";
例如，使用 JDBC 连接到 MySQL 数据库
- MySQLConnUtils.java
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class MySQLConnUtils {
public static Connection getMySQLConnection()
throws ClassNotFoundException, SQLException {
String hostName = "localhost";
String dbName = "learningsql";
String userName = "root";
String password = "12345";
return getMySQLConnection(hostName, dbName, userName, password);
}
public static Connection getMySQLConnection(String hostName, String dbName,
String userName, String password) throws SQLException,
ClassNotFoundException {
// Declare the class Driver for Oracle DB
// This is necessary with Java 5 (or older)
// Java6 (or newer) automatically find the appropriate driver.
// If you use Java> 5, then this line is not needed.
Class.forName("com.mysql.jdbc.Driver");
// Ví dụ: jdbc:mysql://localhost:3306/simplehr
String connectionURL = "jdbc:mysql://" + hostName + ":3306/" + dbName;
Connection conn = DriverManager.getConnection(connectionURL, userName,
password);
return conn;
}
}
3.2- 有些问题出现，如何解决它
在某些情况下，Java连接或另一台计算机链接MySQL会发生出错。其原因可能是没有配置MySQL服务器，以允许其他计算机的连接。
4- JDBC SQLServer (JTDS)
JTDS是另一个SQL Server管理数据库的JDBC库，它是一个开源库。
JTDS是一个开源的100%纯Java(4类)JDBC3.0驱动程序的Microsoft SQL Server(6.5，7，2000，2005，2008，2012)和Sybase ASE(10，11，12，15)。JTDS基于freetds的，目前是SQL Server和Sybase最快生产就绪的JDBC驱动程序。JTDS是100%与JDBC 3.0兼容，只向前和可滚动/可更新结果集支持并执行所有的DatabaseMetaData和ResultSetMetaData方法。
您可以下载JTDS在：
- http://mvnrepository.com/artifact/net.sourceforge.jtds/jtds
结果下载：
4.1- 如何使用(jtds)
使用方法：(用于SQL Server JDBC驱动程序)
// Driver Class net.sourceforge.jtds.jdbc.Driver // Connection URL String: jdbc:jtds::// [: ][/ ][; = [;...]] // Example 1: String url = "jdbc:jtds:sqlserver://MYPC:1433/simplehr;instance=SQLEXPRESS;user=sa;password=s3cr3t"; getConnection(url); // Example 2: String url = "jdbc:jtds:sqlserver://MYPC:1433/simplehr;instance=SQLEXPRESS"; getConnection(url, "sa", "s3cr3t"):
例如，使用JDBC连接到MySQL数据库(用JTDS库)
- SQLServerConnUtils_JTDS.java
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class SQLServerConnUtils_JTDS {
// Connect to SQLServer.
// (Using JTDS library)
public static Connection getSQLServerConnection_JTDS() throws SQLException,
ClassNotFoundException {
String hostName = "localhost";
String sqlInstanceName = "SQLEXPRESS";
String database = "simplehr";
String userName = "sa";
String password = "12345";
return getSQLServerConnection_JTDS(hostName, sqlInstanceName, database,
userName, password);
}
// JTDS & SQLServer.
private static Connection getSQLServerConnection_JTDS(String hostName,
String sqlInstanceName, String database, String userName,
String password) throws ClassNotFoundException, SQLException {
// Declare the class Driver for Oracle DB
// This is necessary with Java 5 (or older)
// Java6 (or newer) automatically find the appropriate driver.
// If you use Java> 5, then this line is not needed.
Class.forName("net.sourceforge.jtds.jdbc.Driver");
// Example:
// jdbc:jtds:sqlserver://localhost:1433/simplehr;instance=SQLEXPRESS
String connectionURL = "jdbc:jtds:sqlserver://" + hostName + ":1433/"
+ database + ";instance=" + sqlInstanceName;
Connection conn = DriverManager.getConnection(connectionURL, userName,
password);
return conn;
}
}
4.2- 有些问题，如何解决它？
在某些情况下，我们连接到SQL Server可能会发生一些错误情况：
Exception in thread "main" java.sql.SQLException: Server tran-vmware has no instance named SQLEXPRESS. at net.sourceforge.jtds.jdbc.JtdsConnection.(JtdsConnection.java:301) at net.sourceforge.jtds.jdbc.Driver.connect(Driver.java:184) at java.sql.DriverManager.getConnection(DriverManager.java:571) at java.sql.DriverManager.getConnection(DriverManager.java:215) at com.yiibai.tutorial.jdbc.ConnectionUtils.getSQLServerConnection_JTDS(ConnectionUtils.java:189) at com.yiibai.tutorial.jdbc.ConnectionUtils.getSQLServerConnection_JTDS(ConnectionUtils.java:72) at com.yiibai.tutorial.jdbc.ConnectionUtils.getMyConnection(ConnectionUtils.java:31) at com.yiibai.tutorial.jdbc.TestConnection.main(TestConnection.java:20)
存在上述错误，因为没有启用SQL Server的TCP/IP服务。
5- JDBC与 SQLServer (SQLJDBC)
SQLJDBC库是由微软提供的。
下载地址：
- http://www.microsoft.com/en-us/download/details.aspx?id=11774
解压刚刚下载的文件。
解压后的结果如下：
5.1- 如何使用 (sqljdbc)
// Driver Class:
com.microsoft.sqlserver.jdbc.SQLServerDriver
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
// Url String:
String url = "jdbc:sqlserver://ServerIp;Instance=SQLEXPRESS;databaseName=simplehr";
// or
String url = "jdbc:sqlserver://ServerIp:1433;Instance=SQLEXPRESS;databaseName=simplehr";
String user = "dbUserID";
String pass = "dbUserPassword";
Connection connection = DriverManager.getConnection(url, user, pass);
例如，使用JDBC连接到SQLServer数据库(用SQLJDBC库)。
- SQLServerConnUtils_SQLJDBC.java
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class SQLServerConnUtils_SQLJDBC {
// Connect to SQLServer.
// (Using SQLJDBC)
public static Connection getSQLServerConnection_SQLJDBC()
throws ClassNotFoundException, SQLException {
String hostName = "localhost";
String sqlInstanceName = "SQLEXPRESS";
String database = "learningsql";
String userName = "sa";
String password = "12345";
return getSQLServerConnection_SQLJDBC(hostName, sqlInstanceName,
database, userName, password);
}
// SQLServer & SQLJDBC.
private static Connection getSQLServerConnection_SQLJDBC(String hostName,
String sqlInstanceName, String database, String userName,
String password) throws ClassNotFoundException, SQLException {
// Declare the class Driver for Oracle DB
// This is necessary with Java 5 (or older)
// Java6 (or newer) automatically find the appropriate driver.
// If you use Java> 5, then this line is not needed.
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
// Example:
// jdbc:sqlserver://ServerIp:1433/SQLEXPRESS;databaseName=simplehr
String connectionURL = "jdbc:sqlserver://" + hostName + ":1433"
+ ";instance=" + sqlInstanceName + ";databaseName=" + database;
Connection conn = DriverManager.getConnection(connectionURL, userName,
password);
return conn;
}
}
5.2- 出现一些麻烦，如何解决它
在某些情况下，我们连接到SQL Server会发生一些错误情况：
com.microsoft.sqlserver.jdbc.SQLServerException: The TCP/IP connection to the host localhost, port 1433 has failed. Error: "Connection refused: connect. Verify the connection properties. Make sure that an instance of SQL Server is running on the host and accepting TCP/IP connections at the port. Make sure that TCP connections to the port are not blocked by a firewall.". at com.microsoft.sqlserver.jdbc.SQLServerException.makeFromDriverError(SQLServerException.java:190) at com.microsoft.sqlserver.jdbc.SQLServerException.ConvertConnectExceptionToSQLServerException(SQLServerException.java:241) at com.microsoft.sqlserver.jdbc.SocketFinder.findSocket(IOBuffer.java:2243) at com.microsoft.sqlserver.jdbc.TDSChannel.open(IOBuffer.java:491) at com.microsoft.sqlserver.jdbc.SQLServerConnection.connectHelper(SQLServerConnection.java:1309) at com.microsoft.sqlserver.jdbc.SQLServerConnection.login(SQLServerConnection.java:991) at com.microsoft.sqlserver.jdbc.SQLServerConnection.connect(SQLServerConnection.java:827) at com.microsoft.sqlserver.jdbc.SQLServerDriver.connect(SQLServerDriver.java:1012) at java.sql.DriverManager.getConnection(Unknown Source) at java.sql.DriverManager.getConnection(Unknown Source) ...
如存在上述错误，因为可能没有启用SQL Server的TCP/IP服务。需要启动SQLServer服务，如果仍然出现以下错误：
Exception in thread "main" com.microsoft.sqlserver.jdbc.SQLServerException: The TCP/IP connection to the host tran-vmware, port 1433 has failed. Error: "Connection refused: connect. Verify the connection properties. Make sure that an instance of SQL Server is running on the host and accepting TCP/IP connections at the port. Make sure that TCP connections to the port are not blocked by a firewall.". at com.microsoft.sqlserver.jdbc.SQLServerException.makeFromDriverError(SQLServerException.java:190) at com.microsoft.sqlserver.jdbc.SQLServerException.ConvertConnectExceptionToSQLServerException(SQLServerException.java:241) at com.microsoft.sqlserver.jdbc.SocketFinder.findSocket(IOBuffer.java:2243) at com.microsoft.sqlserver.jdbc.TDSChannel.open(IOBuffer.java:491) at com.microsoft.sqlserver.jdbc.SQLServerConnection.connectHelper(SQLServerConnection.java:1309) at com.microsoft.sqlserver.jdbc.SQLServerConnection.login(SQLServerConnection.java:991) at com.microsoft.sqlserver.jdbc.SQLServerConnection.connect(SQLServerConnection.java:827) at com.microsoft.sqlserver.jdbc.SQLServerDriver.connect(SQLServerDriver.java:1012) at java.sql.DriverManager.getConnection(DriverManager.java:571) at java.sql.DriverManager.getConnection(DriverManager.java:215) ...
-
您应该考虑使用JTDS了
6- JDBC驱动和MongoDB
JDBC驱动程序MongoDB，你从下面的网址下载：
- https://github.com/mongodb/mongo-java-driver/downloads
您也可以在Maven仓库下载：
- http://mvnrepository.com/artifact/org.mongodb/mongo-java-driver
