java源代码实例
java访问xml文件
<!-- Code highlighting produced by Actipro CodeHighlighter (freeware) http://www.CodeHighlighter.com/ --> import java.io. * ; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.Node; import org.w3c.dom.NodeList; public class xmljava { public static void main(String args[]) { Element element = null ; File f = new File( " a.xml " ); DocumentBuilder db = null ; // documentBuilder为抽象不能直接实例化(将XML文件转换为DOM文件) DocumentBuilderFactory dbf = null ; try { dbf = DocumentBuilderFactory.newInstance(); // 返回documentBuilderFactory对象 db = dbf.newDocumentBuilder(); // 返回db对象用documentBuilderFatory对象获得返回documentBuildr对象 Document dt = db.parse(f); // 得到一个DOM并返回给document对象 element = dt.getDocumentElement(); // 得到一个elment根元素 System.out.println( " 根元素： " + element.getNodeName()); // 获得根节点 NodeList childNodes = element.getChildNodes() ; // 获得根元素下的子节点 for ( int i = 0 ; i < childNodes.getLength(); i ++ ) // 遍历这些子节点 { Node node1 = childNodes.item(i); // childNodes.item(i); 获得每个对应位置i的结点 if ( " Account " .equals(node1.getNodeName())) { // 如果节点的名称为"Account"，则输出Account元素属性type System.out.println( " \r\n找到一篇账号. 所属区域: " + node1.getAttributes().getNamedItem ( " type " ).getNodeValue() + " . " ); NodeList nodeDetail = node1.getChildNodes(); // 获得<Accounts>下的节点 for ( int j = 0 ; j < nodeDetail.getLength(); j ++ ) { // 遍历<Accounts>下的节点 Node detail = nodeDetail.item(j); // 获得<Accounts>元素每一个节点 if ( " code " .equals(detail.getNodeName())) // 输出code System.out.println( " 卡号: " + detail.getTextContent()); else if ( " pass " .equals(detail.getNodeName())) // 输出pass System.out.println( " 密码: " + detail.getTextContent()); else if ( " name " .equals(detail.getNodeName())) // 输出name System.out.println( " 姓名: " + detail.getTextContent()); else if ( " money " .equals(detail.getNodeName())) // 输出money System.out.println( " 余额: " + detail.getTextContent()); } } } } catch (Exception e){System.out.println(e);} }
java jdbc数据库连接<!-- Code highlighting produced by Actipro CodeHighlighter (freeware) http://www.CodeHighlighter.com/ --> <? xml version="1.0" encoding="gbk" ?> < Accounts > < Account type ="by0003" > < code > 100001 </ code > < pass > 123 </ pass > < name > 李四 </ name > < money > 1000000.00 </ money > </ Account > < Account type ="hz0001" > < code > 100002 </ code > < pass > 123 </ pass > < name > 张三 </ name > < money > 1000.00 </ money > </ Account > </ Accounts >
<!-- Code highlighting produced by Actipro CodeHighlighter (freeware) http://www.CodeHighlighter.com/ --> 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; public class JDBConnection { public Connection conn = null ; // 声明Connection对象的实例 public Statement stmt = null ; // 声明Statement对象的实例 public ResultSet rs = null ; // 声明ResultSet对象的实例 private static String dbClassName = " com.microsoft.jdbc.sqlserver.SQLServerDriver " ; // 定义保存数据库驱动的变量 private static String dbUrl = " jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=DB_ATM " ; private static String dbUser = " sa " ; private static String dbPwd = " sa " ; public JDBConnection(String propertyFileName) { // 带属性文件名的构造方法 Properties prop = new Properties(); // 属性集合对象 InputStream is = null ; try { is = JDBConnection. class .getClassLoader().getResourceAsStream( propertyFileName); // 属性文件输入流 // is = new FileInputStream("src/" + propertyFileName); prop.load(is); // 将属性文件流装载到Properties对象中 is.close(); // 关闭流 dbClassName = prop.getProperty( " dbClassName " ); dbUrl = prop.getProperty( " dbUrl " ); dbUser = prop.getProperty( " dbUser " ); dbPwd = prop.getProperty( " dbPwd " ); } catch (Exception e) { System.out.println( " 属性文件 " + propertyFileName + " 打开失败！ " ); } try { Class.forName(dbClassName); // 1.注册驱动 } catch (ClassNotFoundException e) { e.printStackTrace(); } } public JDBConnection() { // 默认的不带参数的构造函数 try { Class.forName(dbClassName); // 1.注册驱动 } catch (ClassNotFoundException e) { e.printStackTrace(); } } public static Connection getConnection() { Connection conn = null ; try { // Class.forName(dbClassName); // 1.注册驱动 conn = DriverManager.getConnection(dbUrl, dbUser, dbPwd); // 2.建立与数据库的链接 } catch (Exception ee) { ee.printStackTrace(); } if (conn == null ) { System.err .println( " 警告: DbConnectionManager.getConnection() 获得数据库链接失败.\r\n\r\n链接类型: " + dbClassName + " \r\n链接位置: " + dbUrl + " \r\n用户/密码 " + dbUser + " / " + dbPwd); } return conn; } /* * 功能：执行查询语句 */ public ResultSet executeQuery(String sql) { try { // 捕捉异常 conn = getConnection(); // 调用getConnection()方法构造Connection对象的一个实例conn stmt = conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, // 3.创建语句 ResultSet.CONCUR_READ_ONLY); rs = stmt.executeQuery(sql); // 4.执行查询 } catch (SQLException ex) { System.err.println(ex.getMessage()); // 输出异常信息 } return rs; // 返回结果集对象 5.结果处理 } /* * 功能:执行更新操作 */ public int executeUpdate(String sql) { int result = 0 ; // 定义保存返回值的变量 try { // 捕捉异常 conn = getConnection(); // 调用getConnection()方法构造Connection对象的一个实例conn stmt = conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_READ_ONLY); result = stmt.executeUpdate(sql); // 执行更新操作 } catch (SQLException ex) { result = 0 ; // 将保存返回值的变量赋值为0 } return result; // 返回保存返回值的变量 } /* * 功能:关闭数据库的连接 */ public void close() { // 6.释放资源 try { // 捕捉异常 try { if (rs != null ) { // 当ResultSet对象的实例rs不为空时 rs.close(); // 关闭ResultSet对象 } } finally { try { if (stmt != null ) { // 当Statement对象的实例stmt不为空时 stmt.close(); // 关闭Statement对象 } } finally { if (conn != null ) { // 当Connection对象的实例conn不为空时 conn.close(); // 关闭Connection对象 } } } } catch (Exception e) { e.printStackTrace(System.err); // 输出异常信息 } } }
属性文件
dbClassName=com.microsoft.jdbc.sqlserver.SQLServerDriver
dbClassName2=com.mysql.jdbc.Driver
dbPwd=sa
dbPwd2=root
dbUrl=jdbc\:microsoft\:sqlserver\://localhost\:1433;DatabaseName\=DB_ATM
dbUrl2=jdbc\:mysql\://localhost\:3306/db_atm
dbUser=sa
dbUser2=root
java自定义按钮外观
<!-- Code highlighting produced by Actipro CodeHighlighter (freeware) http://www.CodeHighlighter.com/ --> import java.awt.FlowLayout; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.UIManager; import javax.swing.plaf.synth.SynthLookAndFeel; public class MyButton { JFrame frame = new JFrame( " Test Buttons " ); JButton jButton = new JButton( " JButton " ); // 按钮 public MyButton() { frame.setLayout( new FlowLayout()); frame.getContentPane().add(jButton); } public void show() { frame.pack(); frame.show(); } public static void main(String[] args) { MyButton tb = new MyButton(); tb.show(); SynthLookAndFeel slf = new SynthLookAndFeel(); try { slf.load(MyButton. class .getResourceAsStream( " mybutton.xml " ), MyButton. class ); UIManager.setLookAndFeel(slf); } catch (Exception e) { e.printStackTrace(); return ; } } }
java访问资源文件<!-- Code highlighting produced by Actipro CodeHighlighter (freeware) http://www.CodeHighlighter.com/ --> < synth > < style id ="mybutton" > < state > < imagePainter method ="buttonBackground" path ="mybutton.png" sourceInsets ="3 6 12 20" paintCenter ="true" stretch ="true" /> < insets top ="3" left ="6" bottom ="12" right ="20" /> < font name ="Aharoni" size ="16" /> </ state > < property key ="Button.margin" type ="insets" value ="0 0 5 8" /> </ style > < bind style ="mybutton" type ="region" key ="Button" /> </ synth >
<!-- Code highlighting produced by Actipro CodeHighlighter (freeware) http://www.CodeHighlighter.com/ --> import java.io.FileInputStream; import java.io.FileOutputStream; import java.util.Properties; public class PropertyEditor { public static void main(String[] args) throws Exception { Properties prop = new Properties(); // 属性集合对象 FileInputStream fis = new FileInputStream( " prop.properties " ); // 属性文件输入流 (相对于根目录下的文件名，要加上包名 “src/prop.properties”) prop.load(fis); // 将属性文件流装载到Properties对象中 fis.close(); // 关闭流 // 获取属性值，sitename已在文件中定义 System.out.println( " 获取属性值：sitename= " + prop.getProperty( " sitename " )); // 获取属性值，country未在文件中定义，将在此程序中返回一个默认值，但并不修改属性文件 System.out.println( " 获取属性值：country= " + prop.getProperty( " country " , " 中国 " )); // 修改sitename的属性值 prop.setProperty( " sitename " , " 中国 " ); // 添加一个新的属性studio prop.setProperty( " studio " , " Boxcode Studio " ); // 文件输出流 FileOutputStream fos = new FileOutputStream( " prop.properties " ); // 将Properties集合保存到流中 prop.store(fos, " Copyright (c) Boxcode Studio " ); fos.close(); // 关闭流 } }
资源文件
sitename=\u4E2D\u56FD
siteurl=www.abcjava.com
studio=Boxcode Studio java日期处理bean
<!-- Code highlighting produced by Actipro CodeHighlighter (freeware) http://www.CodeHighlighter.com/ --> import java.text.ParsePosition; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Date; import java.util.GregorianCalendar; import java.util.regex.Pattern; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; public class DateUtil { protected static Log logger = LogFactory.getLog(DateUtil. class ); // 格式：年－月－日 小时：分钟：秒 public static final String FORMAT_ONE = " yyyy-MM-dd HH:mm:ss " ; // 格式：年－月－日 小时：分钟 public static final String FORMAT_TWO = " yyyy-MM-dd HH:mm " ; // 格式：年月日 小时分钟秒 public static final String FORMAT_THREE = " yyyyMMdd-HHmmss " ; // 格式：年－月－日 public static final String LONG_DATE_FORMAT = " yyyy-MM-dd " ; // 格式：月－日 public static final String SHORT_DATE_FORMAT = " MM-dd " ; // 格式：小时：分钟：秒 public static final String LONG_TIME_FORMAT = " HH:mm:ss " ; // 格式：年-月 public static final String MONTG_DATE_FORMAT = " yyyy-MM " ; // 年的加减 public static final int SUB_YEAR = Calendar.YEAR; // 月加减 public static final int SUB_MONTH = Calendar.MONTH; // 天的加减 public static final int SUB_DAY = Calendar.DATE; // 小时的加减 public static final int SUB_HOUR = Calendar.HOUR; // 分钟的加减 public static final int SUB_MINUTE = Calendar.MINUTE; // 秒的加减 public static final int SUB_SECOND = Calendar.SECOND; static final String dayNames[] = { " 星期日 " , " 星期一 " , " 星期二 " , " 星期三 " , " 星期四 " , " 星期五 " , " 星期六 " }; @SuppressWarnings( " unused " ) private static final SimpleDateFormat timeFormat = new SimpleDateFormat( " yyyy-MM-dd HH:mm:ss " ); public DateUtil() { } /** * 把符合日期格式的字符串转换为日期类型 */ public static java.util.Date stringtoDate(String dateStr, String format) { Date d = null ; SimpleDateFormat formater = new SimpleDateFormat(format); try { formater.setLenient( false ); d = formater.parse(dateStr); } catch (Exception e) { // log.error(e); d = null ; } return d; } /** * 把符合日期格式的字符串转换为日期类型 <分享到：
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