1、Staff实体

public class Staff {    private String name;    private int age;    private String address;    public Staff() {    }    public Staff(String name, int age, String address) {        this.name = name;        this.age = age;        this.address = address;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public int getAge() {        return age;    }    public void setAge(int age) {        this.age = age;    }    public String getAddress() {        return address;    }    public void setAddress(String address) {        this.address = address;    }    @Override    public String toString() {        return "Staff{" +                "name='" + name + '\'' +                ", age=" + age +                ", address='" + address + '\'' +                '}';    }}

 

2、将字符串列表转换为大写

public class TextJava8Map1 {    public static void main(String[] args) {        List
     
       alpha = Arrays.asList("a", "b", "c", "d");        // 在Java8之前        List
      
        alphaUpper = new ArrayList<>();        for (String s :alpha) {            alphaUpper.add(s.toUpperCase());        }        System.out.println(alpha);        System.out.println(alphaUpper);        // Java8 map        List
       
         collect1 = alpha.stream()                .map(String::toUpperCase)                .collect(Collectors.toList());        System.out.println(collect1);    }}
       
      
     

 

3、获取List对象列表中某个属性的集合(Developer在博客-Java8比较器)

public class TextJava8Map2 {    public static void main(String[] args) {        List
     
       developers = Arrays.asList(                new Developer("java", new BigDecimal(23231), 32),                new Developer("c++", new BigDecimal(32432), 30),                new Developer("spring", new BigDecimal(23121), 34)        );        // 在Java8之前        List
      
        names1 = new ArrayList<>();        for (Developer developer : developers) {            names1.add(developer.getName());        }        System.out.println(names1);        // Java8 map        List
       
         names2 = developers.stream()                .map(developer -> developer.getName())                .collect(Collectors.toList());        System.out.println(names2);    }}
       
      
     

 

4、将一个List对象列表转换为另一个List对象列表

public class TextJava8Map3 {    public static void main(String[] args) {        List
     
       developers = Arrays.asList(                new Developer("java", new BigDecimal(23231), 32),                new Developer("c++", new BigDecimal(32432), 30),                new Developer("spring", new BigDecimal(23121), 34)        );        // 在Java8之前        List
      
        staffs = convertToStaff(developers);        System.out.println(staffs);        // Java8 map        List
       
         result = developers.stream()                .map(developer -> {                    Staff staff = new Staff();                    staff.setName(developer.getName());                    staff.setAge(developer.getAge());                    if ("c++".equals(developer.getName())) {                        staff.setAddress("us");                    }                    return staff;                })                .collect(Collectors.toList());        System.out.println(result);    }    private static List
        
          convertToStaff(List
         
           developers) {        List
          
            staffs = new ArrayList<>(); for (Developer developer :developers) { Staff staff = new Staff(); staff.setName(developer.getName()); staff.setAge(developer.getAge()); if ("java".equals(developer.getName())) { staff.setAddress("us"); } staffs.add(staff); } return staffs; }}