java对象属性排序，支持中英文字符串和数字

废话很少说，该类主要实现按对象属性将对象排序，排序能够按任意多属性进行排序，相似sql的order by，还能够设置排序是升序仍是降序。

 

 import java.lang.reflect.Method; import java.text.Collator; import java.util.ArrayList; import java.util.Collections; import java.util.Comparator; import java.util.List; /** * @author 邬小洪 QQ:16044171 * @version 1.0,2010-7-24 */ public class MyComparator implements Comparator { private Comparator cmp = Collator.getInstance(java.util.Locale.CHINA); private String[] sortBy; private int order; private MyComparator(String[] sortBy, int order) { this.sortBy = sortBy; this.order = order; } /* * 定义排序规则 若是按照不止一个属性进行排序 这按照属性的顺序进行排序,相似sql order by 即只要比较出同位置的属性就中止 */ public int compare(Object o1, Object o2) { for (int i = 0; i < sortBy.length; i++) { Object value1 = getFieldValueByName(sortBy[i], o1); Object value2 = getFieldValueByName(sortBy[i], o2); if (value1 instanceof Integer && value2 instanceof Integer) { int v1 = Integer.parseInt(value1.toString()); int v2 = Integer.parseInt(value2.toString()); if (v1 > v2) { return 1 * this.order; } else if (v1 < v2) { return -1 * this.order; } } else { int result = cmp.compare(value1, value2); if (result != 0) { return result * this.order; } } } return -1 * this.order; } /** * * 经过反射，获取属性值 * * @param fieldName * @param o * @return */ private Object getFieldValueByName(String fieldName, Object o) { try { String firstLetter = fieldName.substring(0, 1).toUpperCase(); String getter = "get" + firstLetter + fieldName.substring(1); Method method = o.getClass().getMethod(getter, new Class[] {}); Object value = method.invoke(o, new Object[] {}); return value; } catch (Exception e) { System.out.println("属性不存在"); return null; } } /** * * 待排序对象 * * @author 邬小洪 QQ:16044171 * @version 1.0,2010-7-24 */ private static class Bean { private String name = null; private String post = null; private Integer age = null; public Integer getAge() { return age; } public void setAge(Integer age) { this.age = age; } public String getPost() { return post; } public void setPost(String post) { this.post = post; } public String getName() { return name; } public void setName(String name) { this.name = name; } } public static void main(String[] args) { Bean b1 = new Bean(); b1.setName("邬小洪"); b1.setPost("研发工程师"); b1.setAge(26); Bean b2 = new Bean(); b2.setName("小洪"); b2.setPost("部署工程师"); b2.setAge(27); Bean b3 = new Bean(); b3.setName("洪儿"); b3.setPost("部署工程师"); b3.setAge(28); Bean b4 = new Bean(); b4.setName("邬小洪"); b4.setPost("架构工程师"); b4.setAge(27); List<Bean> list = new ArrayList<Bean>(); list.add(b1); list.add(b2); list.add(b3); list.add(b4); String[] sortBy = new String[] { "name", "post" }; int orderBy = 1;//1:升序，-1：降序 MyComparator myCmp = new MyComparator(sortBy, orderBy); Collections.sort(list, myCmp); System.out.println("--------------------按名字和职位升序----------------------------"); for (Bean b : list) { System.out.println("name:" + b.getName() + ",post:" + b.getPost() + ",age:" + b.getAge()); } sortBy = new String[] { "post", "age" }; myCmp = new MyComparator(sortBy, orderBy); Collections.sort(list, myCmp); System.out.println("--------------------按职位和年龄升序----------------------------"); for (Bean b : list) { System.out.println("post:" + b.getPost() + ",age:" + b.getAge() + ",name:" + b.getName()); } sortBy = new String[] { "age", "name" }; myCmp = new MyComparator(sortBy, orderBy); Collections.sort(list, myCmp); System.out.println("--------------------按年龄和名字升序----------------------------"); for (Bean b : list) { System.out.println("age:" + b.getAge() + ",name:" + b.getName() + ",post:" + b.getPost()); } } }

 

运行结果：

--------------------按名字和职位升序----------------------------
name:洪儿,post:部署工程师,age:28
name:小洪,post:部署工程师,age:27
name:邬小洪,post:研发工程师,age:26
name:邬小洪,post:架构工程师,age:27
--------------------按职位和年龄升序----------------------------
post:部署工程师,age:27,name:小洪
post:部署工程师,age:28,name:洪儿
post:架构工程师,age:27,name:邬小洪
post:研发工程师,age:26,name:邬小洪
--------------------按年龄和名字升序----------------------------
age:26,name:邬小洪,post:研发工程师
age:27,name:小洪,post:部署工程师
age:27,name:邬小洪,post:架构工程师
age:28,name:洪儿,post:部署工程师