用 Java 将装箱数组转换为流的程序

原文:https://www . geesforgeks . org/program-to-convert-box-array-to-stream-in-Java/

一个数组是一组相似类型的变量,它们被一个共同的名字所引用。根据数组的定义,数组可以包含基元数据类型以及类的对象。在原语数据类型的情况下,实际值存储在连续的内存位置。对于类的对象,实际的对象存储在堆段中。

装箱数组是以对象的形式定义的数组,而不是基元。 例:int a = 4;

示例:

输入:数组:【极客、伪造者、电脑入口】 输出:流:【极客、伪造者、电脑入口】

输入:数组:[1,2,3,4,5] 输出:流:[1,2,3,4,5]

以下是用 Java 将装箱数组转换为流的方法:

  1. Using Arrays.stream():

    算法:

    1. 获取要转换的数组。
    2. 通过将数组作为参数传递,使用 Arrays.stream()方法将数组转换为流。
    3. 返回形成的流

    程序:

    ```java // Java Program to convert // Array to Stream

    import java.util.; import java.util.stream.;

    class GFG {

    // Generic function to convert      // an Array to Stream     public static Stream                  convertArrayToStream(T array[])     {

    // Return the converted Stream         return Arrays.stream(array);     }

    public static void main(String args[])     {         // Create an Array         String array[] = { "Geeks", "forGeeks",                                      "A Computer Portal" };

    // Print the Array         System.out.println("Array: "                                 + Arrays.toString(array));

    // convert the Array to Stream         Stream             stream = convertArrayToStream(array);

    // Print the Stream         System.out.println("Stream: "                      + Arrays.toString(stream.toArray()));     } } ```

    Output:

    ```java Array: [Geeks, forGeeks, A computer Portal] Stream: [Geeks, forGeeks, A computer Portal]

    ```

  2. Using Stream.of(): Stream.of() method creates a Stream directly with the values or collection passed as the parameter.

    算法:

    1. 获取要转换的数组。
    2. 通过将数组作为参数传递,使用 Stream.of()方法将数组转换为流。
    3. 返回形成的流

    程序:

    ```java // Java Program to convert // Array to Stream

    import java.util.; import java.util.stream.;

    class GFG {

    // Generic function to convert     // an Array to Stream     public static Stream              convertArrayToStream(T array[])     {

    // Return the converted Stream         return Stream.of(array);     }

    public static void main(String args[])     {         // Create an Array         String array[] = { "Geeks", "forGeeks",                                      "A Computer Portal" };

    // Print the Array         System.out.println("Array: "                             + Arrays.toString(array));

    // convert the Array to Stream         Stream             stream = convertArrayToStream(array);

    // Print the Stream         System.out.println("Stream: "                          + Arrays.toString(stream.toArray()));     } } ```

    Output:

    ```java Array: [Geeks, forGeeks, A computer Portal] Stream: [Geeks, forGeeks, A computer Portal]

    ```

  3. Using List.stream(): This is an indirect method in which the array is first converted into a List using Arrays.asList() method. Then the formed list is converted into a Stream using List.stream() method.

    算法:

    1. 获取要转换的数组。
    2. 通过将数组作为参数传递,使用 Arrays.asList()方法将数组转换为列表。
    3. 使用 List.stream()方法将形成的列表转换为流。
    4. 返回形成的流

    程序:

    ```java // Java Program to convert // Array to Stream

    import java.util.; import java.util.stream.;

    class GFG {

    // Generic function to convert      // an Array to Stream     public static Stream                  convertArrayToStream(T array[])     {

    // Return the converted Stream         return Arrays             .asList(array)             .stream();     }

    public static void main(String args[])     {         // Create an Array         String array[] = { "Geeks", "forGeeks",                                      "A Computer Portal" };

    // Print the Array         System.out.println("Array: "                          + Arrays.toString(array));

    // convert the Array to Stream         Stream             stream = convertArrayToStream(array);

    // Print the Stream         System.out.println("Stream: "                     + Arrays.toString(stream.toArray()));     } } ```

    Output:

    ```java Array: [Geeks, forGeeks, A computer Portal] Stream: [Geeks, forGeeks, A computer Portal]

    ```