常用的函数式接口--Predicate，默认方法negate，or，and，Predicate接口练习--集合信息筛选

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常用的函数式接口–Predicate

package Lambda_Return;import java.util.function.Predicate;public class PredicateDemo {
    public static void main(String[] args) {
    String str="12345";boolean b=checkString(str,(s)->{
    return s.length()>5;});System.out.println(b);}public static boolean checkString(String str, Predicate<String> pre){
    return pre.test(str);}
}

Predicate默认方法and

Predicate默认方法or

Predicate默认方法negate

Predicate接口练习–集合信息筛选

package Lambda_Return;import java.util.ArrayList;
import java.util.function.Predicate;public class PredicateTest {
    public static void main(String[] args) {
    String[] arr={
    "古力娜扎,女","迪丽热巴,女","戈尔马丹,男"};ArrayList<String> stringArrayList=checkString(arr,(s)->{
    String[] split = s.split(",");return split[0].length()==4&&split[1].equals("女");});for (String s : stringArrayList) {
    System.out.println(s);}}public static ArrayList<String> checkString(String[] arr, Predicate<String> pre){
    ArrayList<String> strings = new ArrayList<>();for (String s : arr) {
    if(pre.test(s))strings.add(s);}return strings;}}