📜  字节类 |番石榴 |Java

📅  最后修改于: 2022-05-13 01:55:42.165000             🧑  作者: Mango

字节类 |番石榴 |Java

Bytes是原始类型字节的实用程序类。它提供了与字节原语有关的静态实用程序方法,这些方法在字节或数组中都没有,并将字节解释为既无符号也无符号。在SignedBytesUnsignedBytes中可以找到专门将字节视为有符号或无符号的方法。

宣言 :

@GwtCompatible(emulated=true)
public final class Bytes
extends Object

下表显示了 Guava Bytes Class 提供的方法:

例外:

  • ensureCapacity : IllegalArgumentException如果 minLength 或 padding 为负数。
  • toArray : NullPointerException如果集合或其任何元素为空。

下面给出了一些示例,展示了 Guava Bytes Class 方法的实现:
示例 1:

// Java code to show implementation
// of Guava Bytes.asList() method
  
import com.google.common.primitives.Bytes;
import java.util.*;
  
class GFG {
    // Driver method
    public static void main(String[] args)
    {
        byte arr[] = { 3, 4, 5, 6, 7 };
  
        // Using Bytes.asList() method which convert
        // array of primitives to array of objects
        List myList = Bytes.asList(arr);
  
        // Displaying the elements
        System.out.println(myList);
    }
}

输出 :

[3, 4, 5, 6, 7]

示例 2:

// Java code to show implementation
// of Guava Bytes.indexOf() method
  
import com.google.common.primitives.Bytes;
import java.util.*;
  
class GFG {
    // Driver method
    public static void main(String[] args)
    {
        byte[] arr = { 3, 4, 5, 6, 7 };
  
        // Displaying the index for
        // first occurrence of given target
        System.out.println(Bytes.indexOf(arr, (byte)5));
    }
}

输出 :

2

示例 3:

// Java code to show implementation
// of Guava Bytes.concat() method
  
import com.google.common.primitives.Bytes;
import java.util.*;
  
class GFG {
    // Driver method
    public static void main(String[] args)
    {
        byte[] arr1 = { 3, 4, 5 };
        byte[] arr2 = { 6, 7 };
  
        // Using Bytes.concat() method which
        // combines arrays from specified
        // arrays into a single array
        byte[] arr = Bytes.concat(arr1, arr2);
  
        // Displaying the elements
        System.out.println(Arrays.toString(arr));
    }
}

输出 :

[3, 4, 5, 6, 7]

示例 4:

// Java code to show implementation
// of Guava Bytes.contains() method
  
import com.google.common.primitives.Bytes;
  
class GFG {
    // Driver method
    public static void main(String[] args)
    {
        byte[] arr = { 3, 4, 5, 6, 7 };
  
        // Using Bytes.contains() method which
        // checks if element is present in array
        // or not
        System.out.println(Bytes.contains(arr, (byte)8));
        System.out.println(Bytes.contains(arr, (byte)7));
    }
}

输出 :

false
true

示例 5:

// Java code to show implementation
// of Guava Bytes.lastIndexOf() method
  
import com.google.common.primitives.Bytes;
  
class GFG {
    // Driver method
    public static void main(String[] args)
    {
        byte[] arr = { 3, 4, 5, 6, 7, 5, 5 };
  
        // Using Bytes.lastIndexOf() method
        // to get last occurrence of given target
        System.out.println(Bytes.lastIndexOf(arr, (byte)5));
    }
}

输出 :

6

示例 6:

// Java code to show implementation
// of Guava Bytes.lastIndexOf() method
  
import com.google.common.primitives.Bytes;
  
class GFG {
    // Driver method
    public static void main(String[] args)
    {
        byte[] arr = { 3, 4, 5, 6, 7, 5, 5 };
  
        // Using Bytes.lastIndexOf() method
        // to get last occurrence of given target
        // here target i.e, 9 is not present in
        // array arr, so -1 will be returned
        System.out.println(Bytes.lastIndexOf(arr, (byte)9));
    }
}

输出 :

-1