开发中有时候需要自己封装分页排序时,List如何对某一属性排序呢,分享一个小实例,大家共勉,希望能对大家有用,请多多指教。
1.Student的Bean如下:
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public class Student { private int age; private String name; private String weight; public String getWeight() { return weight; } public void setWeight(String weight) { this .weight = weight; } public int getAge() { return age; } public void setAge( int age) { this .age = age; } public String getName() { return name; } public void setName(String name) { this .name = name; } } |
2.按照List中对象的Int类型属性进行排序
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/** * 按照List中的某个Int类型的属性进行排序 * @param list */ @SuppressWarnings ( "unchecked" ) public static void sortIntMethod(List list){ Collections.sort(list, new Comparator(){ @Override public int compare(Object o1, Object o2) { Student stu1=(Student)o1; Student stu2=(Student)o2; if (stu1.getAge()>stu2.getAge()){ return 1 ; } else if (stu1.getAge()==stu2.getAge()){ return 0 ; } else { return - 1 ; } } }); System.out.println( "/////////////排序之后///////////////" ); for ( int i= 0 ;i<list.size();i++){ Student st=(Student)list.get(i); System.out.println( "st.age=" +st.getAge()+ ",st.name=" +st.getName()); } } |
3.按照List中对象的String类型的属性进行排序
1)方法一:
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/** * 按照List中的某个String类型的属性进行排序 * @param list */ @SuppressWarnings ( "unchecked" ) public static void sortStringMethod(List list){ Collections.sort(list, new Comparator(){ @Override public int compare(Object o1, Object o2) { Student stu1=(Student)o1; Student stu2=(Student)o2; return stu1.getName().compareTo(stu2.getName()); } }); System.out.println( "/////////////排序之后///////////////" ); for ( int i= 0 ;i<list.size();i++){ Student st=(Student)list.get(i); System.out.println( "st.age=" +st.getAge()+ ",st.name=" +st.getName()); } } |
2)方法二:
使用java.text.RuleBasedCollator来实现,用来执行区分语言环境的String 比较:
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/** * 按照List中的某个String类型的属性进行排序 * @param list */ @SuppressWarnings ( "unchecked" ) public static void sortByRuleBasedCollator(List list){ Collections.sort(list, new Comparator(){ @Override public int compare(Object o1, Object o2) { return ((java.text.RuleBasedCollator)java.text.Collator.getInstance(java.util.Locale.CHINA)).compare(((Student)o1).getName(), ((Student)o2).getName()); } }); System.out.println( "/////////////排序之后///////////////" ); for ( int i= 0 ;i<list.size();i++){ Student st=(Student)list.get(i); System.out.println( "st.age=" +st.getAge()+ ",st.name=" +st.getName()); } } |
4.测试排序的方法
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@SuppressWarnings ( "unchecked" ) public static void main(String[] args) { ArrayList list= new ArrayList(); Student t1= new Student(); t1.setAge( 35 ); t1.setName( "wanglei" ); list.add(t1); Student t2= new Student(); t2.setAge( 4 ); t2.setName( "lisi" ); list.add(t2); Student t3= new Student(); t3.setAge( 56 ); t3.setName( "zhonghua" ); list.add(t3); Student t4= new Student(); t4.setAge( 39 ); t4.setName( "waanglei" ); list.add(t4); System.out.println( "/////////////排序之前///////////////" ); for ( int i= 0 ;i<list.size();i++){ Student st=(Student)list.get(i); System.out.println( "st.age=" +st.getAge()+ ",st.name=" +st.getName()); } //按照List中的某个Int类型的属性进行排序 sortIntMethod(list); //按照List中的某个String类型的属性进行排序 sortStringMethod(list); } |
5.结果