apache commons工具集代码详解

//1、 克隆对象 // 新创建一个普通Java Bean，用来作为被克隆的对象 public class Person {	private String name = "";	private String email = "";	private int age;	//省略 set,get方法}// 再创建一个Test类，其中在main方法中代码如下： import java.lang.reflect.InvocationTargetException;import java.util.HashMap;import java.util.Map;import org.apache.commons.beanutils.BeanUtils;import org.apache.commons.beanutils.ConvertUtils;public class Test {	/**   * @param args   */	public static void main(String[] args) {		Person person = new Person();		person.setName("tom");		person.setAge(21);		try {			//克隆 			Person person2 = (Person)BeanUtils.cloneBean(person);			System.out.println(person2.getName()+">>"+person2.getAge());		}		catch (IllegalAccessException e) {			e.printStackTrace();		}		catch (InstantiationException e) {			e.printStackTrace();		}		catch (InvocationTargetException e) {			e.printStackTrace();		}		catch (NoSuchMethodException e) {			e.printStackTrace();		}	}}// 原理也是通过Java的反射机制来做的。 // 2、 将一个Map对象转化为一个Bean // 这个Map对象的key必须与Bean的属性相对应。 Map map = new HashMap();map.put("name","tom");map.put("email","tom@");map.put("age","21");//将map转化为一个Person对象 Person person = new Person();BeanUtils.populate(person,map);// 通过上面的一行代码，此时person的属性就已经具有了上面所赋的值了。 // 将一个Bean转化为一个Map对象了，如下： Map map = BeanUtils.describe(person)

//1、 将JavaBean转为XML内容 // 新创建一个Person类 public class Person{	private String name;	private int age;	/** Need to allow bean to be created via reflection */	public PersonBean() {	}	public PersonBean(String name, int age) {		this.name = name;		this.age = age;	}	//省略set, get方法 	public String toString() {		return "PersonBean[name='" + name + "',age='" + age + "']";	}}//再创建一个WriteApp类： import java.io.StringWriter;import org.apache.commons.betwixt.io.BeanWriter;public class WriteApp {	/**   * 创建一个例子Bean，并将它转化为XML.   */	public static final void main(String [] args) throws Exception {		// 先创建一个StringWriter，我们将把它写入为一个字符串     		StringWriter outputWriter = new StringWriter();		// Betwixt在这里仅仅是将Bean写入为一个片断 		// 所以如果要想完整的XML内容，我们应该写入头格式 		outputWriter.write(“<?xml version='1.0′ encoding='UTF-8′ ?>/n”);		// 创建一个BeanWriter，其将写入到我们预备的stream中 		BeanWriter beanWriter = new BeanWriter(outputWriter);		// 配置betwixt 		// 更多详情请参考java docs 或最新的文档 		beanWriter.getXMLIntrospector().getConfiguration().setAttributesForPrimitives(false);		beanWriter.getBindingConfiguration().setMapIDs(false);		beanWriter.enablePrettyPrint();		// 如果这个地方不传入XML的根节点名，Betwixt将自己猜测是什么 		// 但是让我们将例子Bean名作为根节点吧 		beanWriter.write(“person”, new PersonBean(“John Smith”, 21));		//输出结果 		System.out.println(outputWriter.toString());		// Betwixt写的是片断而不是一个文档，所以不要自动的关闭掉writers或者streams， 		//但这里仅仅是一个例子，不会做更多事情，所以可以关掉 		outputWriter.close();	}}//2、 将XML转化为JavaBean import java.io.StringReader;import org.apache.commons.betwixt.io.BeanReader;public class ReadApp {	public static final void main(String args[]) throws Exception{		// 先创建一个XML，由于这里仅是作为例子，所以我们硬编码了一段XML内容 		StringReader xmlReader = new StringReader( 		    "<?xml version='1.0′ encoding='UTF-8′ ?> <person><age>25</age><name>James Smith</name></person>");		//创建BeanReader 		BeanReader beanReader = new BeanReader();		//配置reader 		beanReader.getXMLIntrospector().getConfiguration().setAttributesForPrimitives(false);		beanReader.getBindingConfiguration().setMapIDs(false);		//注册beans，以便betwixt知道XML将要被转化为一个什么Bean 		beanReader.registerBeanClass("person", PersonBean.class);		//现在我们对XML进行解析 		PersonBean person = (PersonBean) beanReader.parse(xmlReader);		//输出结果 		System.out.println(person);	}}

//Base64编解码 private static String encodeTest(String str){	Base64 base64 = new Base64();	try {		str = base64.encodeToString(str.getBytes("UTF-8"));	}	catch (UnsupportedEncodingException e) {		e.printStackTrace();	}	System.out.println("Base64 编码后："+str);	return str;}private static void decodeTest(String str){	Base64 base64 = new Base64();	//str = Arrays.toString(Base64.decodeBase64(str)); 	str = new String(Base64.decodeBase64(str));	System.out.println("Base64 解码后："+str);}

/**     * 得到集合里按顺序存放的key之后的某一Key     */OrderedMap map = new LinkedMap();map.put("FIVE", "5");map.put("SIX", "6");map.put("SEVEN", "7");map.firstKey();// returns "FIVE" map.nextKey("FIVE");// returns "SIX" map.nextKey("SIX");// returns "SEVEN"  /**     * 通过key得到value     * 通过value得到key     * 将map里的key和value对调     */BidiMap bidi = new TreeBidiMap();bidi.put("SIX", "6");bidi.get("SIX");// returns "6" bidi.getKey("6");// returns "SIX" //    bidi.removeValue("6"); // removes the mapping BidiMap inverse = bidi.inverseBidiMap();// returns a map with keys and values swapped System.out.println(inverse);/**      * 得到两个集合中相同的元素      */List<String> list1 = new ArrayList<String>();list1.add("1");list1.add("2");list1.add("3");List<String> list2 = new ArrayList<String>();list2.add("2");list2.add("3");list2.add("5");Collection c = CollectionUtils.retainAll(list1, list2);System.out.println(c);

//创建压缩对象 ZipArchiveEntry entry = new ZipArchiveEntry("CompressTest");//要压缩的文件 File f=new File("e://test.pdf");FileInputStream fis=new FileInputStream(f);//输出的对象 压缩的文件 ZipArchiveOutputStream zipOutput=new ZipArchiveOutputStream(new File("e://test.zip"));zipOutput.putArchiveEntry(entry);int i=0,j;while((j=fis.read()) != -1)    {	zipOutput.write(j);	i++;	System.out.println(i);}zipOutput.closeArchiveEntry();zipOutput.close();fis.close();

//举一个Properties的简单例子 # usergui.properties colors.background = #FFFFFF colors.foreground = #000080 window.width = 500 window.height = 300 PropertiesConfiguration config = new PropertiesConfiguration("usergui.properties");config.setProperty("colors.background", "#000000); config.save(); config.save("usergui.backup.properties);//save a copy Integer integer = config.getInteger("window.width");

import javax.sql.DataSource;import java.sql.Connection;import java.sql.Statement;import java.sql.ResultSet;import java.sql.SQLException;import org.apache.commons.pool.ObjectPool;import org.apache.commons.pool.impl.GenericObjectPool;import org.apache.commons.dbcp.ConnectionFactory;import org.apache.commons.dbcp.PoolingDataSource;import org.apache.commons.dbcp.PoolableConnectionFactory;import org.apache.commons.dbcp.DriverManagerConnectionFactory;//官方示例 public class PoolingDataSources {	public static void main(String[] args) {		System.out.println("加载jdbc驱动");		try {			Class.forName("oracle.jdbc.driver.OracleDriver");		}		catch (ClassNotFoundException e) {			e.printStackTrace();		}		System.out.println("Done.");		// 		System.out.println("设置数据源");		DataSource dataSource = setupDataSource("jdbc:oracle:thin:@localhost:1521:test");		System.out.println("Done.");		// 		Connection conn = null;		Statement stmt = null;		ResultSet rset = null;		try {			System.out.println("Creating connection.");			conn = dataSource.getConnection();			System.out.println("Creating statement.");			stmt = conn.createStatement();			System.out.println("Executing statement.");			rset = stmt.executeQuery("select * from person");			System.out.println("Results:");			int numcols = rset.getMetaData().getColumnCount();			while(rset.next()) {				for (int i=0;i<=numcols;i++) {					System.out.print("/t" + rset.getString(i));				}				System.out.println("");			}		}		catch(SQLException e) {			e.printStackTrace();		}		finally {			try {				if (rset != null) rset.close();			}			catch(Exception e) {			}			try {				if (stmt != null) stmt.close();			}			catch(Exception e) {			}			try {				if (conn != null) conn.close();			}			catch(Exception e) {			}		}	}	public static DataSource setupDataSource(String connectURI) {		//设置连接地址 		ConnectionFactory connectionFactory = new DriverManagerConnectionFactory( 		        connectURI, null);		// 创建连接工厂 		PoolableConnectionFactory poolableConnectionFactory = new PoolableConnectionFactory( 		        connectionFactory);		//获取GenericObjectPool 连接的实例 		ObjectPool connectionPool = new GenericObjectPool( 		        poolableConnectionFactory);		// 创建 PoolingDriver 		PoolingDataSource dataSource = new PoolingDataSource(connectionPool);		return dataSource;	}}

import org.apache.commons.dbutils.DbUtils;import org.apache.commons.dbutils.QueryRunner;import org.apache.commons.dbutils.handlers.BeanListHandler;import java.sql.Connection;import java.sql.DriverManager;import java.sql.SQLException;import java.util.List;//转换成list public class BeanLists {	public static void main(String[] args) {		Connection conn = null;		String url = "jdbc:mysql://localhost:3306/ptest";		String jdbcDriver = "com.mysql.jdbc.Driver";		String user = "root";		String password = "ptest";		DbUtils.loadDriver(jdbcDriver);		try {			conn = DriverManager.getConnection(url, user, password);			QueryRunner qr = new QueryRunner();			List results = (List) qr.query(conn, "select id,name from person", new BeanListHandler(Person.class));			for (int i = 0; i < results.size(); i++) {				Person p = (Person) results.get(i);				System.out.println("id:" + p.getId() + ",name:" + p.getName());			}		}		catch (SQLException e) {			e.printStackTrace();		}		finally {			DbUtils.closeQuietly(conn);		}	}}public class Person{	private Integer id;	private String name;	//省略set, get方法}import org.apache.commons.dbutils.DbUtils;import org.apache.commons.dbutils.QueryRunner;import org.apache.commons.dbutils.handlers.MapListHandler;import java.sql.Connection;import java.sql.DriverManager;import java.sql.SQLException;import java.util.List;import java.util.Map;//转换成map public class MapLists {	public static void main(String[] args) {		Connection conn = null;		String url = "jdbc:mysql://localhost:3306/ptest";		String jdbcDriver = "com.mysql.jdbc.Driver";		String user = "root";		String password = "ptest";		DbUtils.loadDriver(jdbcDriver);		try {			conn = DriverManager.getConnection(url, user, password);			QueryRunner qr = new QueryRunner();			List results = (List) qr.query(conn, "select id,name from person", new MapListHandler());			for (int i = 0; i < results.size(); i++) {				Map map = (Map) results.get(i);				System.out.println("id:" + map.get("id") + ",name:" + map.get("name"));			}		}		catch (SQLException e) {			e.printStackTrace();		}		finally {			DbUtils.closeQuietly(conn);		}	}}

//用commons email发送邮件 public static void main(String args[]){	Email email = new SimpleEmail();	email.setHostName("smtp.googlemail.com");	email.setSmtpPort(465);	email.setAuthenticator(new DefaultAuthenticator("username", "password"));	email.setSSLOnConnect(true);	email.setFrom("user@gmail.com");	email.setSubject("TestMail");	email.setMsg("This is a test mail ... :-)");	email.addTo("foo@bar.com");	email.send();}

//官方示例： //* 检查请求是否含有上传文件 // Check that we have a file upload request Boolean isMultipart = ServletFileUpload.isMultipartContent(request);//现在我们得到了items的列表 //如果你的应用近于最简单的情况，上面的处理就够了。但我们有时候还是需要更多的控制。 //下面提供了几种控制选择： // Create a factory for disk-based file items DiskFileItemFactory factory = new DiskFileItemFactory();// Set factory constraints factory.setSizeThreshold(yourMaxMemorySize);factory.setRepository(yourTempDirectory);// Create a new file upload handler ServletFileUpload upload = new ServletFileUpload(factory);// 设置最大上传大小 upload.setSizeMax(yourMaxRequestSize);// 解析所有请求 List /* FileItem */items = upload.parseRequest(request);// Create a factory for disk-based file items DiskFileItemFactory factory = new DiskFileItemFactory(       yourMaxMemorySize, yourTempDirectory);//一旦解析完成，你需要进一步处理item的列表。 // Process the uploaded items Iterator iter = items.iterator();while (iter.hasNext()) {	FileItem item = (FileItem) iter.next();	if (item.isFormField()) {		processFormField(item);	} else {		processUploadedFile(item);	}}//区分数据是否为简单的表单数据，如果是简单的数据： // processFormField if (item.isFormField()) {	String name = item.getFieldName();	String value = item.getString();	//...省略步骤}//如果是提交的文件： // processUploadedFile if (!item.isFormField()) {	String fieldName = item.getFieldName();	String fileName = item.getName();	String contentType = item.getContentType();	Boolean isInMemory = item.isInMemory();	long sizeInBytes = item.getSize();	//...省略步骤}//对于这些item，我们通常要把它们写入文件，或转为一个流 // Process a file upload if (writeToFile) {	File uploadedFile = new File(...);	item.write(uploadedFile);} else {	InputStream uploadedStream = item.getInputStream();	//...省略步骤 	uploadedStream.close();}//或转为字节数组保存在内存中： // Process a file upload in memory byte[] data = item.get();//...省略步骤 //如果这个文件真的很大，你可能会希望向用户报告到底传了多少到服务端，让用户了解上传的过程 //Create a progress listener ProgressListener progressListener = new ProgressListener(){	public void update(long pBytesRead, long pContentLength, int pItems) {		System.out.println("We are currently reading item " + pItems);		if (pContentLength == -1) {			System.out.println("So far, " + pBytesRead + " bytes have been read.");		} else {			System.out.println("So far, " + pBytesRead + " of " + pContentLength 			                 + " bytes have been read.");		}	}};upload.setProgressListener(progressListener);

//GET方法 import java.io.IOException;import org.apache.commons.httpclient.*;import org.apache.commons.httpclient.methods.GetMethod;import org.apache.commons.httpclient.params.HttpMethodParams;public class GetSample{	public static void main(String[] args) {		// 构造HttpClient的实例 		HttpClient httpClient = new HttpClient();		// 创建GET方法的实例 		GetMethod getMethod = new GetMethod("http://www.ibm.com");		// 使用系统提供的默认的恢复策略 		getMethod.getParams().setParameter(HttpMethodParams.RETRY_HANDLER, 		        new DefaultHttpMethodRetryHandler());		try {			// 执行getMethod 			int statusCode = httpClient.executeMethod(getMethod);			if (statusCode != HttpStatus.SC_OK) {				System.err.println("Method failed: " 				            + getMethod.getStatusLine());			}			// 读取内容 			byte[] responseBody = getMethod.getResponseBody();			// 处理内容 			System.out.println(new String(responseBody));		}		catch (HttpException e) {			// 发生致命的异常，可能是协议不对或者返回的内容有问题 			System.out.println("Please check your provided http address!");			e.printStackTrace();		}		catch (IOException e) {			// 发生网络异常 			e.printStackTrace();		}		finally {			// 释放连接 			getMethod.releaseConnection();		}	}}//POST方法 import java.io.IOException;import org.apache.commons.httpclient.*;import org.apache.commons.httpclient.methods.PostMethod;import org.apache.commons.httpclient.params.HttpMethodParams;public class PostSample{	public static void main(String[] args) {		// 构造HttpClient的实例 		HttpClient httpClient = new HttpClient();		// 创建POST方法的实例 		String url = "http://www.oracle.com/";		PostMethod postMethod = new PostMethod(url);		// 填入各个表单域的值 		NameValuePair[] data = { new NameValuePair("id", "youUserName"), 		    new NameValuePair("passwd", "yourPwd")	}	;	// 将表单的值放入postMethod中 	postMethod.setRequestBody(data);	// 执行postMethod 	int statusCode = httpClient.executeMethod(postMethod);	// HttpClient对于要求接受后继服务的请求，象POST和PUT等不能自动处理转发 	// 301或者302 	if (statusCode == HttpStatus.SC_MOVED_PERMANENTLY ||  	    statusCode == HttpStatus.SC_MOVED_TEMPORARILY) {		// 从头中取出转向的地址 		Header locationHeader = postMethod.getResponseHeader("location");		String location = null;		if (locationHeader != null) {			location = locationHeader.getValue();			System.out.println("The page was redirected to:" + location);		} else {			System.err.println("Location field value is null.");		}		return;	}}}

//1．读取Stream //标准代码： InputStream in = new URL( "http://jakarta.apache.org" ).openStream();try {	InputStreamReader inR = new InputStreamReader( in );	BufferedReader buf = new BufferedReader( inR );	String line;	while ( ( line = buf.readLine() ) != null ) {		System.out.println( line );	}}finally {	in.close();}//使用IOUtils InputStream in = new URL( "http://jakarta.apache.org" ).openStream();try {	System.out.println( IOUtils.toString( in ) );}finally {	IOUtils.closeQuietly(in);}//2．读取文件 File file = new File("/commons/io/project.properties");List lines = FileUtils.readLines(file, "UTF-8");//3．察看剩余空间 long freeSpace = FileSystemUtils.freeSpace("C:/");

// 1 合并两个数组: org.apache.commons.lang. ArrayUtils // 有时我们需要将两个数组合并为一个数组，用ArrayUtils就非常方便，示例如下： private static void testArr() {	String[] s1 = new String[] { "1", "2", "3" };	String[] s2 = new String[] { "a", "b", "c" };	String[] s = (String[]) ArrayUtils.addAll(s1, s2);	for (int i = 0; i < s.length; i++) {		System.out.println(s[i]);	}	String str = ArrayUtils.toString(s);	str = str.substring(1, str.length() - 1);	System.out.println(str + ">>" + str.length());}//2 截取从from开始字符串 StringUtils.substringAfter("SELECT * FROM PERSON ", "from");//3 判断该字符串是不是为数字(0~9)组成，如果是，返回true 但该方法不识别有小数点和 请注意 StringUtils.isNumeric("454534");//返回true //4.取得类名 System.out.println(ClassUtils.getShortClassName(Test.class));//取得其包名 System.out.println(ClassUtils.getPackageName(Test.class));//5.NumberUtils System.out.println(NumberUtils.stringToint("6"));//6.五位的随机字母和数字 System.out.println(RandomStringUtils.randomAlphanumeric(5));//7.StringEscapeUtils System.out.println(StringEscapeUtils.escapeHtml("<html>"));//输出结果为<html> System.out.println(StringEscapeUtils.escapeJava("String"));//8.StringUtils,判断是否是空格字符 System.out.println(StringUtils.isBlank("  "));//将数组中的内容以,分隔 System.out.println(StringUtils.join(test,","));//在右边加下字符,使之总长度为6 System.out.println(StringUtils.rightPad("abc", 6, 'T'));//首字母大写 System.out.println(StringUtils.capitalize("abc"));//Deletes all whitespaces from a String 删除所有空格 System.out.println( StringUtils.deleteWhitespace("  ab c "));//判断是否包含这个字符 System.out.println( StringUtils.contains("abc", "ba"));//表示左边两个字符 System.out.println( StringUtils.left("abc", 2));System.out.println(NumberUtils.stringToint("33"));

import org.apache.commons.logging.Log;import org.apache.commons.logging.LogFactory;public class CommonLogTest {	private static Log log = LogFactory.getLog(CommonLogTest.class);	//日志打印 	public static void main(String[] args) {		log.error("ERROR");		log.debug("DEBUG");		log.warn("WARN");		log.info("INFO");		log.trace("TRACE");		System.out.println(log.getClass());	}}

// 获取日期验证 DateValidator validator = DateValidator.getInstance();// 验证/转换日期 Date fooDate = validator.validate(fooString, "dd/MM/yyyy");if (fooDate == null) {	// 错误 不是日期 	return;}

// 设置参数 Boolean caseSensitive = false;String regex1  = "^([A-Z]*)(?://-)([A-Z]*)*$"    String regex2  = "^([A-Z]*)$";String[] regexs = new String[] {regex1, regex1};// 创建验证 RegexValidator validator = new RegexValidator(regexs, caseSensitive);// 验证返回boolean Boolean valid = validator.isValid("abc-def");// 验证返回字符串 String result = validator.validate("abc-def");// 验证返回数组 String[] groups = validator.match("abc-def");

<form-validation>   <global>     <validator name="required"      classname="org.apache.commons.validator.TestValidator"      method="validateRequired"      methodParams="java.lang.Object, org.apache.commons.validator.Field"/>   </global>   <formset>   </formset> </form-validation>  添加姓名验证.  <form-validation>   <global>     <validator name="required"      classname="org.apache.commons.validator.TestValidator"      method="validateRequired"      methodParams="java.lang.Object, org.apache.commons.validator.Field"/>   </global>   <formset>     <form name="nameForm">      <field property="firstName" depends="required">        <arg0 key="nameForm.firstname.displayname"/>      </field>      <field property="lastName" depends="required">        <arg0 key="nameForm.lastname.displayname"/>      </field>     </form>   </formset> </form-validation>  

Excerpts from org.apache.commons.validator.RequiredNameTest //加载验证配置文件 InputStream in = this.getClass().getResourceAsStream("validator-name-required.xml");ValidatorResources resources = new ValidatorResources(in);//这个是自己创建的bean 我这里省略了 Name name = new Name();Validator validator = new Validator(resources, "nameForm");//设置参数 validator.setParameter(Validator.BEAN_PARAM, name);Map results = null;//验证 results = validator.validate();if (results.get("firstName") == null) {	//验证成功} else {	//有错误   int errors = ((Integer)results.get("firstName")).intValue();}