if ((startLong >>> 8 & 0xFF) >0&& (startLong >>> 24 & 0xFF) <= 126) { System.out.println("- 子网类型: A"); } else if ((startLong >>> 16 & 0xFF) >128&& (startLong >>> 24 & 0xFF) <= 191) { System.out.println("- 子网类型: B"); } else if ((startLong >>> 24 & 0xFF) >192&& (startLong >>> 24 & 0xFF) <= 223) { System.out.println("- 子网类型: C"); } else { System.out.println("- 无法判断类型"); }帮我修改代码,让它能够判断正确的类型
时间: 2023-12-10 11:40:34 浏览: 55
根据IP地址的第一个字节来判断子网类型可以使用以下代码:
```
if ((startLong >>> 24 & 0xFF) >=1&& (startLong >>> 24 & 0xFF) <= 126) {
System.out.println("- 子网类型: A");
} else if ((startLong >>> 24 & 0xFF) >=128&& (startLong >>> 24 & 0xFF) <= 191) {
System.out.println("- 子网类型: B");
} else if ((startLong >>> 24 & 0xFF) >=192&& (startLong >>> 24 & 0xFF) <= 223) {
System.out.println("- 子网类型: C");
} else {
System.out.println("- 无法判断类型");
}
```
这里我们使用了位运算符 `>>>` 来获取无符号的整数值。同时,我们也修改了判断条件,使其能够正确地判断子网类型。
相关问题
System.out.println("子网地址:"+subnet); System.out.println("- 起始地址: " + startAddress); System.out.println("- 结束地址: " + endAddress); System.out.println("- 广播地址: " + broadcastAddress); System.out.println( "- 新子网掩码: " + longToIp((0xFFFFFFFF << (32 - subnetMaskLengthRequired)) & 0xFFFFFFFF)); System.out.println("- 借位数: " + (subnetMaskLengthRequired - subnetMaskLength)); System.out.println("- 子网大小: " +subnetSize ); // 判断子网是A类、B类、还是C类地址 // 判断子网是A类、B类、还是C类地址 // 判断子网是A类、B类、还是C类地址 if (startLong >>> 24 == 0) { System.out.println("- Subnet Class: A"); } else if (startLong >>> 16 == 172 && (startLong >>> 20 & 0xF) >= 1 && (startLong >>> 20 & 0xF) <= 14) { System.out.println("- Subnet Class: B"); } else if ((startLong >>> 24 & 0xFF) >192&& (startLong >>> 24 & 0xFF) <= 223) { System.out.println("- Subnet Class: C"); } else { System.out.println("- Unknown subnet class"); }帮我把结果改成表格形式输出的Java代码
下面是将结果改为表格形式输出的Java代码:
```
System.out.println("+---------------+------------------------+------------------------+------------------------+------------------------+------------------+----------------------+");
System.out.println("| Subnet Mask | Subnet Address | Start Address | End Address | Broadcast Address | Subnet Class | Subnet Size |");
System.out.println("+---------------+------------------------+------------------------+------------------------+------------------------+------------------+----------------------+");
System.out.printf("| %d | %15s | %15s | %15s | %15s | %16s | %20s |\n", subnetMaskLengthRequired, subnet, startAddress, endAddress, broadcastAddress, subnetClass, subnetSize);
System.out.println("+---------------+------------------------+------------------------+------------------------+------------------------+------------------+----------------------+");
```
请注意,此代码假定您已经定义并初始化了变量subnetMaskLengthRequired、subnet、startAddress、endAddress、broadcastAddress、subnetClass和subnetSize。
macMsg->Buffer[bufItr++] = ( macMsg->MIC >> 24 ) & 0xFF;什么意思
这行代码是将一个32位的消息完整性代码(MIC)的高8位存入一个消息缓冲区(macMsg->Buffer)中,并将缓冲区指针(bufItr)向后移动一位。具体解释如下:
- `(macMsg->MIC >> 24)`:将MIC右移24位,即取出MIC的高8位。
- `& 0xFF`:将结果与0xFF(二进制11111111)进行按位与操作,将MIC高8位以外的位全部清零,保留MIC高8位的值。
- `(macMsg->Buffer[bufItr++] = ...)`:将上述结果存入消息缓冲区(macMsg->Buffer)中,并将缓冲区指针(bufItr)向后移动一位,方便下一次存储操作。注意,这是一个赋值表达式,其结果为存储的值,即MIC的高8位。
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