Predicate接口在Java的lambda表达式中的重要性？
Predicate<T>是一个泛型函数接口，表示单个参数函数，该函数返回布尔值（true或false）。此接口在java.util.function包中可用，并且包含用于评估给定参数谓词的test（Tt）方法。
语法
public interface Predicate {
boolean test(T t);
}示例
import java.util.*;
import java.util.functionPredicate;
public class LambdaPredicateTest {
public static void main(String args[]) {
Employee emp1 = new Employee("Raja", 26);
Employee emp2 = new Employee("Jaidev", 24);
Employee emp3 = new Employee("Adithya", 30);
List<Employee> empList = new ArrayList<Employee>();
empList.add(emp1);
empList.add(emp2);
empList.add(emp3);
Predicate<Employee> predicateForAge = (e) -> e.age >= 25;
Predicate<Employee> predicateForName = (e) -> e.name.startsWith("A");
for(Employee emp : empList) {
if(predicateForAge.test(emp)) {
System.out.println(emp.name +" is eligible by age");
}
}
System.out.println("----------------------------");
for(Employee emp : empList) {
if(predicateForName.test(emp)) {
System.out.println(emp.name +" is eligible by name");
}
}
}
}// Employee classclass Employee {
public String name;
public int age;
public Employee(String name,int age){
this.name=name;
this.age=age;
}
}输出结果
Raja is eligible by age Adithya is eligible by age ---------------------------- Adithya is eligible by name