不多说直接上代码

public static void getHostFrom(String url) {
        Pattern p = Pattern.compile("jdbc:(?<db>\\w+):.*((//)|@)(?<host>.+):(?<port>\\d+)(/|(;DatabaseName=)|:)(?<dbName>\\w+)\\??.*");
        Matcher m = p.matcher(url);
        if(m.find()) {
            System.out.println(m.group("db"));
            System.out.println(m.group("host"));
            System.out.println(m.group("port"));
            System.out.println(m.group("dbName"));
        }
        
}
public static void main(String[] args) {
		getHostFrom("jdbc:mysql://127.0.0.1:3306/databaseName");
		getHostFrom("jdbc:microsoft:sqlserver://127.0.0.1:1433;DatabaseName=databaseName");
		getHostFrom("jdbc:oracle:thin:@localhost:1521:dbName");
		
}

具体原理参照：Java String.ReplaceAll捕获组用法(正则表达式捕获组及命名捕获组)

转自：https://www.cnblogs.com/activiti/p/6703478.html
1、Oracle8/8i/9i数据库（thin模式）

Class.forName(“oracle.jdbc.driver.OracleDriver”).newInstance();
String url=“jdbc:oracle:thin:@localhost:1521:orcl”;
//orcl为数据库的SID
String user=“test”;
String password=“test”;
Connection conn= DriverManager.getConnection(url,user,password);

2、DB2数据库

Class.forName(“com.ibm.db2.jdbc.app.DB2Driver “).newInstance();
String url=“jdbc:db2://localhost:5000/sample”;
//sample为你的数据库名
String user=“admin”;
String password=””;
Connection conn= DriverManager.getConnection(url,user,password);

3、Sql Server7.0/2000数据库

Class.forName(“com.microsoft.jdbc.sqlserver.SQLServerDriver”).newInstance();
String url=“jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=mydb”;
//mydb为数据库
String user=“sa”;
String password="";
Connection conn= DriverManager.getConnection(url,user,password);

4、Sybase数据库

Class.forName(“com.sybase.jdbc.SybDriver”).newInstance();
String url =" jdbc:sybase:Tds:localhost:5007/myDB";
//myDB为你的数据库名
Properties sysProps = System.getProperties();
SysProps.put(“user”,“userid”);
SysProps.put(“password”,“user_password”);
Connection conn= DriverManager.getConnection(url, SysProps);

5、Informix数据库

Class.forName(“com.informix.jdbc.IfxDriver”).newInstance();
String url = "jdbc:informix-sqli://123.45.67.89:1533/myDB:INFORMIXSERVER=myserver;

user=testuser;password=testpassword"; //myDB为数据库名
Connection conn= DriverManager.getConnection(url);

6、MySQL数据库

Class.forName(“org.gjt.mm.mysql.Driver”).newInstance();&
Class.forName(“com.mysql.jdbc.Driver”);
String url =“jdbc:mysql://localhost/myDB?user=soft&password=soft1234&useUnicode=true&characterEncoding=8859_1”
//myDB为数据库名
Connection conn= DriverManager.getConnection(url);

7、PostgreSQL数据库

Class.forName(“org.postgresql.Driver”).newInstance();
String url =“jdbc:postgresql://localhost/myDB”
//myDB为数据库名
String user=“myuser”;
String password=“mypassword”;
Connection conn= DriverManager.getConnection(url,user,password);

8、access数据库直连用ODBC的

Class.forName(“sun.jdbc.odbc.JdbcOdbcDriver”) ;
String url=“jdbc:odbc:Driver={MicroSoft Access Driver (*.mdb)};
DBQ=”+application.getRealPath("/Data/ReportDemo.mdb");
Connection conn = DriverManager.getConnection(url,"","");
Statement stmtNew=conn.createStatement() ;

另一种

Microsoft SQL Server
Microsoft SQL Server 驱动程序包名：msbase.jar mssqlserver.jar msutil.jar
驱动程序类名: com.microsoft.JDBC jdbc:microsoft:sqlserver://<server_name>:
默认端口1433，如果服务器使用默认端口则port可以省略

Microsoft SQL Server 2005 驱动程序包名：sqljdbc.jar
驱动程序类名: com.microsoft.sqlserver.JDBC jdbc:sqlserver://<server_name>:
默认端口1433，如果服务器使用默认端口则port可以省略

Oracle
Oracle Thin 驱动程序包名：ojdbc14.jar
驱动程序类名: oracle.JDBC URL:
jdbc:oracle:thin:@//:/ServiceName
或
jdbc:oracle:thin:@::

IBM DB2
IBM DB2 Universal Driver Type 4
驱动程序包名：db2jcc.jar db2jcc_license_cu.jar
驱动程序类名: com.ibm.db2.jcc.DB2Driver
URL: database_name>

IBM DB2 Universal Driver Type 2
驱动程序包名：db2jcc.jar db2jcc_license_cu.jar
驱动程序类名: com.ibm.db2.jcc.DB2Driver
URL: database_name>

MySQL
MySQL Connector/J Driver
驱动程序包名：mysql-connector-java-x.x.xx-bin.jar
驱动程序类名: com.mysql.JDBC jdbc:mysql://:/<database_name>
默认端口3306，如果服务器使用默认端口则port可以省略
MySQL Connector/J Driver 允许在jdbc:mysql://:/<database_name>?property1=value1&property2=value2

Informix
Informix 驱动程序包名：ifxjdbc.jar
驱动程序类名: com.informix.JDBC jdbc:informix-sqli://{|}:[/]: INFORMIXSERVER=

Sybase
Sybase Adaptive Server Enterprise 驱动程序包名：jconn2.jar 或jconn3.jar
驱动程序类名: com.sybase.jdbc.SybDriver (com.sybase.jdbc.SybDriver)
URL: jdbc:sybase:Tds::默认端口5000

Sybase Adaptive Server Anywhere or Sybase IQ 驱动程序包名：jconn2.jar 或jconn3.jar
驱动程序类名: com.sybase.jdbc.SybDriver (com.sybase.jdbc.SybDriver)
URL: database_name>
默认端口2638

PostgreSQL
PostgreSQL Native 驱动程序包名：驱动程序类名: org.postgresql.Driver
URL: database_name>
默认端口5432

Teradata
Teradata Driver for the 驱动程序包名：terajdbc4.jar tdgssjava.jar gui.jar
驱动程序类名: com.ncr.teradata.TeraDriver
URL:
Type 4: jdbc:teradata://GatewayServerName:PortNumber
/DatabaseServerName/Param1,Param2,…

Netezza
Netezza 驱动程序包名：terajdbc4.jar tdgssjava.jar gui.jar
驱动程序类名: org.netezza.Driver
URL: database_name>