Sample code and precautions for using JDBC to connect to a database in Java
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The example code is as follows:
Import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.util.ArrayList; import java.util.List; import javax.sql.PooledConnection; import oracle.jdbc.pool.OracleConnectionPoolDataSource; public class JDBCTest {private String url = null / * * / public JDBCTest (String sHostName, String sPortNumber, String sSid) {url = "jdbc:oracle:thin:@" + sHostName + ":" + sPortNumber + ":" + sSid; / / if JDK1.6 you also can use as / / url = "jdbc:oracle:thin:@" + sHostName + ":" + sPortNumber + "/" + sSid } public List getList (String sUsrName, String sPassword, String sql) {List resultList = new ArrayList (); try {OracleConnectionPoolDataSource ocpds = new OracleConnectionPoolDataSource (); String url1 = System.getProperty ("JDBC_URL"); if (url1! = null) url = url1; ocpds.setURL (url) Ocpds.setUser (sUsrName); ocpds.setPassword (sPassword); PooledConnection pc = ocpds.getPooledConnection (); Connection conn = pc.getConnection (); PreparedStatement pstmt = conn.prepareStatement (sql); ResultSet rset = pstmt.executeQuery (); while (rset.next ()) {resultList.add (rset.getString (1)) } rset.close (); pstmt.close (); conn.close (); pc.close ();} catch (Exception e) {} return resultList } / * * @ param args * / public static void main (String [] args) {/ / use you real info String sUsrName = ""; String sPassword = ""; String sql = ""; JDBCTest jdbctest = new JDBCTest ("localhost", "1521", "orcl"); List list = jdbctest.getList (sUsrName, sPassword, sql) System.out.println (list.size ());}}
Special attention should be paid to:
Url = "jdbc:oracle:thin:@" + sHostName + ":" + sPortNumber + "/" + sSid
In JDK1.6, you can use url. That is, port and sid can be separated by "/". You can't use this in JDK 1.5, you can only use ":".
In addition to using the above connection pool to connect, of course, you can also use the traditional way to connect.
Class.forName ("oracle.jdbc.driver.OracleDriver"). NewInstance (); Connection conn = DriverManager.getConnection (url, suUserName,passWord); at this point, I believe you have a deeper understanding of "sample code and precautions for connecting to a database using JDBC in Java". You might as well do it in practice. Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!
