Java番石榴 | Bytes.indexOf(byte[] array, byte[] target) 方法和例子
Guava 的 Bytes 类的Bytes.indexOf(byte[] array, byte[] target)方法接受两个参数array和target 。如果目标存在于数组中,则该方法返回其第一次出现的开始位置。如果数组中不存在目标,则该方法返回-1 。
句法:
public static int indexOf(byte[] array, byte[] target)
参数:该方法接受两个参数:
- 数组:这是要检查目标数组索引的整数数组。
- target:作为指定数组的子序列要搜索的数组。
返回值:该方法返回一个整数值,如下所示:
- 如果目标数组存在于数组中,则返回目标第一次出现的起始位置。
- 否则,如果数组中不存在目标,则返回-1 。
异常:该方法不抛出任何异常。
下面的例子说明了上述方法的实现:
示例 1:
// Java code to show implementation of
// Guava's Bytes.indexOf(byte[] array,
// byte[] target) method
import com.google.common.primitives.Bytes;
import java.util.Arrays;
class GFG {
// Driver's code
public static void main(String[] args)
{
// Creating an byte array
byte[] arr = { 1, 2, 3, 4, 3, 5 };
byte[] target = { 3, 4, 3 };
System.out.println("Array: "
+ Arrays.toString(arr));
System.out.println("Target Array: "
+ Arrays.toString(target));
// Using Bytes.indexOf(byte[] array, byte[] target)
// method to get the start position of the first
// occurrence of the specified target within array,
// or -1 if there is no such occurrence.
int index = Bytes.indexOf(arr, target);
if (index != -1) {
System.out.println("Target is present at index "
+ index);
}
else {
System.out.println("Target is not present "
+ "in the array");
}
}
}
输出:
Array: [1, 2, 3, 4, 3, 5]
Target Array: [3, 4, 3]
Target is present at index 2
示例 2:
// Java code to show implementation of
// Guava's Bytes.indexOf(byte[] array,
// byte[] target) method
import com.google.common.primitives.Bytes;
import java.util.Arrays;
class GFG {
// Driver's code
public static void main(String[] args)
{
// Creating an byte array
byte[] arr = { 3, 5, 7, 11, 13 };
byte[] target = { 23, 37 };
System.out.println("Array: "
+ Arrays.toString(arr));
System.out.println("Target Array: "
+ Arrays.toString(target));
// Using Bytes.indexOf(byte[] array, byte[] target)
// method to get the start position of the first
// occurrence of the specified target within array,
// or -1 if there is no such occurrence.
int index = Bytes.indexOf(arr, target);
if (index != -1) {
System.out.println("Target is present at index "
+ index);
}
else {
System.out.println("Target is not present"
+ " in the array");
}
}
}
输出:
Array: [3, 5, 7, 11, 13]
Target Array: [23, 37]
Target is not present in the array
参考: https://google.github.io/guava/releases/19.0/api/docs/com/google/common/primitives/Bytes.html#indexOf(byte[], %20byte[])