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java访问xml文件

Java code

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);}

}
}

XML code

<?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>
java jdbc数据库连接

Java code

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

Java code

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;
}

}
}

XML code

<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>

java访问资源文件

Java code

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=   
studio=Boxcode Studio
java日期处理bean

Java code

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 mons.logging.Log;
import mons.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
*/
public static java.util.Date stringtoDate(String dateStr, String format,
ParsePosition pos) {
Date d = null;
SimpleDateFormat formater = new SimpleDateFormat(format);
try {
formater.setLenient(false);
d = formater.parse(dateStr, pos);
} catch (Exception e) {
d = null;
}
return d;
}

/**
* 把日期转换为字符串
*/
public static String dateToString(java.util.Date date, String format) {
String result = "";
SimpleDateFormat formater = new SimpleDateFormat(format);
try {
result = formater.format(date);
} catch (Exception e) {
// log.error(e);
}
return result;
}

/**
* 获取当前时间的指定格式
*/
public static String getCurrDate(String format) {
return dateToString(new Date(), format);
}

public static String dateSub(int dateKind, String dateStr, int amount) {
Date date = stringtoDate(dateStr, FORMAT_ONE);
Calendar calendar = Calendar.getInstance();
calendar.setTime(date);
calendar.add(dateKind, amount);
return dateToString(calendar.getTime(), FORMAT_ONE);
}

/**
* 两个日期相减
* @return 相减得到的秒数
*/
public static long timeSub(String firstTime, String secTime) {
long first = stringtoDate(firstTime, FORMAT_ONE).getTime();
long second = stringtoDate(secTime, FORMAT_ONE).getTime();
return (second - first) / 1000;
}

/**
* 获得某月的天数
*/
public static int getDaysOfMonth(String year, String month) {
int days = 0;
if (month.equals("1") || month.equals("3") || month.equals("5")
|| month.equals("7") || month.equals("8") || month.equals("10")
|| month.equals("12")) {
days = 31;
} else if (month.equals("4") || month.equals("6") || month.equals("9")
|| month.equals("11")) {
days = 30;
} else {
if ((Integer.parseInt(year) % 4 == 0 && Integer.parseInt(year) % 100 != 0)
|| Integer.parseInt(year) % 400 == 0) {
days = 29;
} else {
days = 28;
}
}

return days;
}

/**
* 获取某年某月的天数
*/
public static int getDaysOfMonth(int year, int month) {
Calendar calendar = Calendar.getInstance();
calendar.set(year, month - 1, 1);
return calendar.getActualMaximum(Calendar.DAY_OF_MONTH);
}

/**
* 获得当前日期
*/
public static int getToday() {
Calendar calendar = Calendar.getInstance();
return calendar.get(Calendar.DATE);
}

/**
* 获得当前月份
*/
public s