Encapsulating the JDBC Tool class

The basic steps of the JDBC connection database are fixed, so you can consider encapsulating a tool class to simplify database operations.

The use of the properties of Java in the package configuration file, is a key-value pair in the form of the existence, you can connect the database to dynamic information to the inside, so it is more intuitive, not error-prone, and easy to maintain.

Put the configuration file under SRC, if you want to put it under the package, the relative path of the configuration file must start with the package name.

Demo:

Db.properties

mysqldriver=com.mysql.jdbc.drivermysqlurl=jdbc:mysql://localhost:3306/student?useunicode=true& Characterencoding=utf8mysqluser=rootmysqlpwd=1234oracledriver=oracle.jdbc.driver.oracledriveroracleurl=jdbc\:o Racle\:thin\: @localhost \:1521\:orcloracleuser=scottoraclepwd=tiger

Jdbcutil.java

Package Com.wxisme.jdbcutil;import Java.io.closeable;import Java.io.filenotfoundexception;import Java.io.ioexception;import Java.io.inputstream;import Java.sql.connection;import Java.sql.DriverManager;import Java.sql.resultset;import java.sql.sqlexception;import Java.sql.statement;import java.util.Properties;/** * JDBC Database Operations Tool class simplifies database operations * @author Wxisme * */public class Jdbcutil {//resource file static Properties Pros = null;//static initialization when loading Jdbcutil class, call static {pros = new Properties (); try {//Load resource file InputStream in = Thread.CurrentThread (). Getcontextclassloader (). getre Sourceasstream ("Db.properties"), if (in = = null) {throw new FileNotFoundException ("config file not found");} Pros.load (in);} catch (IOException e) {e.printstacktrace ();}} /** * Get database connection * @return Connection */public static Connection getmysqlconnection () {Connection conn = null;try {//Load Database driver C Lass.forname (Pros.getproperty ("Mysqldriver"));//Get database Connection conn = Drivermanager.getconnection (Pros.getproperty (" Mysqlurl "), Pros.getproperty (" Mysqluser "), Pros.getproperty ("Mysqlpwd"));} catch (ClassNotFoundException e) {e.printstacktrace ();} catch (SQLException e) {e.printstacktrace ();} Return conn;} public static Connection Getoracleconn () {try {class.forname (Pros.getproperty ("Oracledriver")); return Drivermanager.getconnection (Pros.getproperty ("Oracleurl"), Pros.getproperty ("Oracleuser"), Pros.getProperty (" Oraclepwd "));} catch (Exception e) {e.printstacktrace (); return null;}}  /** * Close IO resource * @param io */public static void CloseFile (closeable ... io) {for (closeable Temp:io) {if (temp! = null) {try {Temp.close ();} catch (IOException e) {System.out.println ("file close failed"); E.printstacktrace ();}}} Close the JDBC resource note order public static void Close (ResultSet rs,statement ps,connection conn) {try {if (rs!=null) {rs.close ();}} CATC H (SQLException e) {e.printstacktrace ();} try {if (ps!=null) {ps.close ();}} catch (SQLException e) {e.printstacktrace ();} try {if (conn!=null) {conn.close ();}} catch (SQLException e) {e.printstacktrace ()}} public static void Close (Statement ps,connection conn) {TRy {if (ps!=null) {ps.close ();}} catch (SQLException e) {e.printstacktrace ();} try {if (conn!=null) {conn.close ();}} catch (SQLException e) {e.printstacktrace ()}} public static void Close (Connection conn) {try {if (conn!=null) {Conn.close ()}} catch (SQLException e) {E.printstacktrace ();}}}

Utiltest.java

Package Com.wxisme.jdbcutil;import Java.sql.connection;import Java.sql.preparedstatement;import Java.sql.ResultSet Import Java.sql.sqlexception;public class Utiltest {public static void main (string[] args) {Connection conn = jdbcutil.ge Tmysqlconnection (); PreparedStatement PS = null; ResultSet rs = null; String sql = "SELECT * from student where id =?"; try {PS = conn.preparestatement (sql);p S.setint (1, 1), rs = Ps.executequery (), while (Rs.next ()) {System.out.println ( Rs.getstring ("name"));}} catch (SQLException e) {e.printstacktrace ();}}}

It can also be further encapsulated as a thread-safe tool class.

Encapsulating the JDBC Tool class