一)此包的下载 http://commons.apache.org/beanutils/download_beanutils.cgi 此包目前最新的版本是1.8.3 二)此包的功能 用于处理JavaBeans。它利用Java的反射机制,从动态的生成对bean的getter和setter的调用代码,到模拟创建一个动态的bean,等等。这个包看似简单,却是很多开源项目的基石:如在著名的Struts和Spring Framework中,我们都能找到BeanUtils的影子。 三)此包的API http://commons.apache.org/beanutils/v1.8.3/apidocs/index.html 从 1.7.0 版本开始 BeanUtils被细分成3种架包: commons-beanutils.jar - 包含所有BeanUtils内容的架包 commons-beanutils-core.jar - 除去Collections内容的架包 commons-beanutils-bean-collections.jar - 仅有Collections内容的架包(此部分内容依赖于Commons Collections ) 四)常用类: DynaBean -- 该接口定义的是一个动态的JavaBean,它的属性类型、名称和值都是可以动态改变的。 DynaClass -- 该接口定义的是针对实现了DynaBean接口的类的java.lang.Class对象,提供如getName()、newInstance()等方法。 DynaProperty -- 用于描述DynaBean的属性 五)代码样例 Java代码 /** Address.java */ package sean.study.commons.beanutils; public class Address { private String zipCode; private String addr; private String city; private String country; public Address() {} public Address(String zipCode, String addr, String city, String country) { this.zipCode = zipCode; this.addr = addr; this.city = city; this.country = country; } public String getAddr() { return addr; } public void setAddr(String addr) { this.addr = addr; } public String getCity() { return city; } public void setCity(String city) { this.city = city; } public String getCountry() { return country; } public void setCountry(String country) { this.country = country; } public String getZipCode() { return zipCode; } public void setZipCode(String zipCode) { this.zipCode = zipCode; } } /** Customer.java */ package sean.study.commons.beanutils; public class Customer { private long id; private String name; private Address[] addresses; public Customer() {} public Customer(long id, String name, Address[] addresses) { this.id = id; this.name = name; this.addresses = addresses; } public Address[] getAddresses() { return addresses; } public void setAddresses(Address[] addresses) { this.addresses = addresses; } public long getId() { return id; } public void setId(long id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } } 我们来看看通常我们是怎样利用Commons BeanUtils来完成一些基本的JavaBean和DynaBean操作: Java代码 package sean.study.commons.beanutils; import org.apache.commons.beanutils.BasicDynaBean; import org.apache.commons.beanutils.BasicDynaClass; import org.apache.commons.beanutils.DynaBean; import org.apache.commons.beanutils.DynaProperty; import org.apache.commons.beanutils.PropertyUtils; import org.apache.commons.lang.StringUtils; public class BeanUtilsUsage { public static void main(String[] args) throws Exception { demoNormalJavaBeans(); demoDynaBeans(); } public static void demoNormalJavaBeans() throws Exception { System.out.println(StringUtils.center(" demoNormalJavaBeans ", 40, "=")); // data setup Address addr1 = new Address("CA1234", "xxx", "Los Angeles", "USA"); Address addr2 = new Address("100000", "xxx", "Beijing", "China"); Address[] addrs = new Address[2]; addrs[0] = addr1; addrs[1] = addr2; Customer cust = new Customer(123, "John Smith", addrs); // accessing the city of first address String cityPattern = "addresses[0].city"; String name = (String) PropertyUtils.getSimpleProperty(cust, "name"); String city = (String) PropertyUtils.getProperty(cust, cityPattern); Object[] rawOutput1 = new Object[] { "The city of customer ", name, "'s first address is ", city, "." }; System.out.println(StringUtils.join(rawOutput1)); // setting the zipcode of customer's second address String zipPattern = "addresses[1].zipCode"; if (PropertyUtils.isWriteable(cust, zipPattern)) {//PropertyUtils System.out.println("Setting zipcode ..."); PropertyUtils.setProperty(cust, zipPattern, "200000");//PropertyUtils } String zip = (String) PropertyUtils.getProperty(cust, zipPattern);//PropertyUtils Object[] rawOutput2 = new Object[] { "The zipcode of customer ", name, "'s second address is now ", zip, "." }; System.out.println(StringUtils.join(rawOutput2)); System.out.println(); } public static void demoDynaBeans() throws Exception { System.out.println(StringUtils.center(" demoDynaBeans ", 40, "=")); // creating a DynaBean DynaProperty[] dynaBeanProperties = new DynaProperty[] {//DynaProperty new DynaProperty("name", String.class), new DynaProperty("inPrice", Double.class), new DynaProperty("outPrice", Double.class), }; BasicDynaClass cargoClass = new BasicDynaClass("Cargo", BasicDynaBean.class, dynaBeanProperties); //BasicDynaClass BasicDynaBean DynaBean cargo = cargoClass.newInstance();//DynaBean // accessing a DynaBean cargo.set("name", "Instant Noodles"); cargo.set("inPrice", new Double(21.3)); cargo.set("outPrice", new Double(23.8)); System.out.println("name: " + cargo.get("name")); System.out.println("inPrice: " + cargo.get("inPrice")); System.out.println("outPrice: " + cargo.get("outPrice")); System.out.println(); } } 上述代码运行结果如下: ========= demoNormalJavaBeans ========== The city of customer John Smith's first address is Los Angeles. Setting zipcode ... The zipcode of customer John Smith's second address is now 200000. ============ demoDynaBeans ============= name: Instant Noodles inPrice: 21.3 outPrice: 23.8
Commons BeanUtils
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转载自xiaoshanjnby.iteye.com/blog/2077810
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