Java IntBuffer limit()方法及示例

java.nio.IntBuffer类的 limit() 方法是用来修改这个IntBuffer的极限。这个方法以要设置的极限为参数，并将其设置为这个Buffer的新极限。如果这个Buffer的标记已经被定义，并且大于新指定的极限，那么这个新的极限就不会被设置并被丢弃。

语法

public final IntBuffer limit(int newLimit)

参数： 该方法需要一个整数类型的参数newLimit，指的是要设置为缓冲区的新极限。

返回值： 该方法在将指定的新极限设置为该缓冲区的新极限后返回该缓冲区。

下面是limit()方法的例子。

例子 1 :

// Java program to demonstrate// limit() method  import java.nio.*;import java.util.*;  public class GFG {    public static void main(String[] args)    {        // defining and allocating IntBuffer        // using allocate() method        IntBuffer intBuffer            = IntBuffer.allocate(4);          // put int value in IntBuffer        // using put() method        intBuffer.put(20);        intBuffer.put(30);          // print the int buffer        System.out.println(            "IntBuffer before "            + "setting buffer's limit: "            + Arrays.toString(                  intBuffer.array())            + "\nPosition: "            + intBuffer.position()            + "\nLimit: "            + intBuffer.limit());          // Limit the intBuffer        // using limit() method        intBuffer.limit(1);          // print the int buffer        System.out.println(            "\nintBuffer after "            + "setting buffer's limit: "            + Arrays.toString(                  intBuffer.array())            + "\nPosition: "            + intBuffer.position()            + "\nLimit: "            + intBuffer.limit());    }}

输出:

IntBuffer before setting buffer's limit: [20, 30, 0, 0]Position: 2Limit: 4intBuffer after setting buffer's limit: [20, 30, 0, 0]Position: 1Limit: 1

例子 2 :

// Java program to demonstrate// limit() method  import java.nio.*;import java.util.*;  public class GFG {    public static void main(String[] args)    {        // defining and allocating IntBuffer        // using allocate() method        IntBuffer intBuffer            = IntBuffer.allocate(5);          // put int value in IntBuffer        // using put() method        intBuffer.put(20);        intBuffer.put(30);        intBuffer.put(40);          // mark will be going to        // discarded by limit()        intBuffer.mark();          // print the int buffer        System.out.println(            "intBuffer before "            + "setting buffer's limit: "            + Arrays.toString(                  intBuffer.array())            + "\nPosition: "            + intBuffer.position()            + "\nLimit: "            + intBuffer.limit());          // Limit the intBuffer        // using limit() method        intBuffer.limit(4);          // print the int buffer        System.out.println(            "\nintBuffer before "            + "setting buffer's limit: "            + Arrays.toString(                  intBuffer.array())            + "\nPosition: "            + intBuffer.position()            + "\nLimit: "            + intBuffer.limit());    }}

输出:

intBuffer before setting buffer's limit: [20, 30, 40, 0, 0]Position: 3Limit: 5intBuffer before setting buffer's limit: [20, 30, 40, 0, 0]Position: 3Limit: 4

参考资料: https://docs.oracle.com/javase/9/docs/api/java/nio/IntBuffer.html#limit-int-