• Java数组,去掉重复值、增加、删除数组元素


    import java.util.List;
    import java.util.ArrayList;
    import java.util.Set;
    import java.util.HashSet;
    public class lzwCode {
    
        public static void main(String [] args) {
            testA();
            System.out.println("===========================");
            testB();
            System.out.println("===========================");
            testC();
        }
    
        //去掉数组中重复的值
        public static void testA() {
            String [] str = {"Java", "C++", "Php", "C#", "Python", "C++", "Java"};
            for (String elementA:str ) {
                System.out.print(elementA + " ");
            }
            List<String> list = new ArrayList<String>();
            for (int i=0; i<str.length; i++) {
                if(!list.contains(str[i])) {
                    list.add(str[i]);
                }
            }
            /*
            Set<String> set = new HashSet<String>();
            for (int i=0; i<str.length; i++) {
                set.add(str[i]);
            }
            String[] newStr =  set.toArray(new String[1]); 
            */
            System.out.println();
            String[] newStr =  list.toArray(new String[1]); //返回一个包含所有对象的指定类型的数组 
            for (String elementB:newStr ) {
                System.out.print(elementB + " ");
            }
            System.out.println();
        }
    
        //删除数组中其中一个元素
        public static void testB() {
            String [] str = {"Java", "C++", "Php", "C#", "Python"};
            for (String elementA:str ) {
                System.out.print(elementA + " ");
            }
            //删除php
            List<String> list = new ArrayList<String>();
            for (int i=0; i<str.length; i++) {
                list.add(str[i]);
            }
            list.remove(2); //list.remove("Php") 
            System.out.println();
            String[] newStr =  list.toArray(new String[1]); //返回一个包含所有对象的指定类型的数组 
            for (String elementB:newStr ) {
                System.out.print(elementB + " ");
            }    
            System.out.println();
        }
    
        //在数组中增加一个元素
        public static void testC() {
            String [] str = {"Java", "C++", "Php", "C#", "Python"};
            for (String elementA:str ) {
                System.out.print(elementA + " ");
            }
            //增加ruby
            List<String> list = new ArrayList<String>();
            for (int i=0; i<str.length; i++) {
                list.add(str[i]);
            }
            list.add(2, "ruby"); //list.add("ruby") 
            System.out.println();
            String[] newStr =  list.toArray(new String[1]); //返回一个包含所有对象的指定类型的数组 
            for (String elementB:newStr ) {
                System.out.print(elementB + " ");
            }    
            System.out.println();
        }
    }

    ps:http://blog.csdn.net/lzwjavaphp/article/details/6998453

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  • 原文地址:https://www.cnblogs.com/maxinliang/p/5008723.html
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