Java IntStream.Builder accept()方法

IntStream.Builder accept(int t)用于在流的构建阶段向元素中插入一个元素。它接受一个元素到正在构建的流中。

语法

void accept(int t)

参数。该方法接受一个强制性参数 t ，即要输入到流中的元素。

异常： 当构建器已经过渡到构建状态时，该方法会抛出 IllegalStateException 。这意味着流已经进入了构建阶段，现在不能改变。因此， 没有更多的元素可以被接受到流中 。

下面是一些例子来说明accept()方法。

例1 :

// Java code to show the implementation// of IntStream.Builder accept(int t)  import java.util.stream.IntStream;  class GFG {      // Driver code    public static void main(String[] args)    {          // Declaring an empty Stream        IntStream.Builder b = IntStream.builder();          // Inserting elements into the stream        // using IntStream.Builder accept(int t)        b.accept(4);        b.accept(5);        b.accept(6);        b.accept(7);          // Creating the Stream        // The stream has now entered the built phase        // printing the elements        System.out.println("Stream successfully built");        b.build().forEach(System.out::println);    }}

输出。

Stream successfully built4567

例2： 为了说明IllegalStateException

// Java code to show the implementation// of IntStream.Builder accept(int t)  import java.util.stream.IntStream;  class GFG {      // Driver code    public static void main(String[] args)    {          // Declaring an empty Stream        IntStream.Builder b = IntStream.builder();          // using IntStream.Builder accept(int t)        b.accept(4);        b.accept(5);        b.accept(6);        b.accept(7);          // Creating the Stream        // The stream has now entered the built phase        // printing the elements        System.out.println("Stream successfully built");        b.build().forEach(System.out::println);          // Trying to accept another element into the stream        // Since the Stream is in built phase        // This operation is not possible now        // Hence accept() will throw exception now          try {            b.accept(50);        }        catch (Exception e) {            System.out.println("Exception thrown "                               + "when now accepting element into the stream: "                               + e);        }    }}

输出。

Stream successfully built4567Exception thrown when now accepting element into the stream: java.lang.IllegalStateException