四个字节转无符号整型java,从2或4个字节转换为有符号/无符号short / int

四个字节转无符号整型Java可以使用如下代码：

public static long bytesToUnsignedInt(byte[] bytes) {
    long value = 0;
    for (int i = 0; i < bytes.length; i++) {
        value += ((long) bytes[i] & 0xffL) << (8 * i);
    }
    return value;
}

对于2或4个字节转换为有符号/无符号short/int，可以使用Java中的ByteBuffer类进行转换。以下是示例代码：

// 2字节有符号short转换为无符号short
short signedShort = -1;
int unsignedShort = Short.toUnsignedInt(signedShort);

// 4字节有符号int转换为无符号int
int signedInt = -1;
long unsignedInt = Integer.toUnsignedLong(signedInt);

// 2字节无符号short转换为有符号short
int unsignedShort = 65535;
short signedShort = (short) unsignedShort;

// 4字节无符号int转换为有符号int
long unsignedInt = 4294967295L;
int signedInt = (int) unsignedInt;