匹配和查询
boolean anyMatch(Predicate<? super T> predicate)
只要有一个条件满足即返回true
boolean allMatch(Predicate<? super T> predicate)
必须全部都满足才会返回true
boolean noneMatch(Predicate<? super T> predicate)
全都不满足才会返回true
import java.util.List;
import java.util.function.Predicate;
public class MatchDemo {
public static void main(String[] args) {
Predicate<Employee> p1 = e -> e.id < 10 && e.name.startsWith("A");
Predicate<Employee> p2 = e -> e.sal < 10000;
List<Employee> list = Employee.getEmpList();
//using allMatch
boolean b1 = list.stream().allMatch(p1);
System.out.println(b1); //false
boolean b2 = list.stream().allMatch(p2);
System.out.println(b2); //true
//using anyMatch
boolean b3 = list.stream().anyMatch(p1);
System.out.println(b3); //true
boolean b4 = list.stream().anyMatch(p2);
System.out.println(b4); //true
//using noneMatch
boolean b5 = list.stream().noneMatch(p1);
System.out.println(b5); //false
}
}
import java.util.ArrayList;
import java.util.List;
public class Employee {
public int id;
public String name;
public int sal;
public Employee(int id,String name,int sal ){
this.id = id;
this.name = name;
this.sal = sal;
}
public static List<Employee> getEmpList(){
List<Employee> list = new ArrayList<>();
list.add(new Employee(1, "A", 2000));
list.add(new Employee(2, "B", 3000));
list.add(new Employee(3, "C", 4000));
list.add(new Employee(4, "D", 5000));
return list;
}
}
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