java官方提供了一种操作字节数组的方法——内存流(字节数组流)ByteArrayInputStream、ByteArrayOutputStream
ByteArrayOutputStream——byte数组合并
/**
* 将所有的字节数组全部写入内存中,之后将其转化为字节数组
*/
public static void main(String[] args) throws IOException {
String str1 = "132";
String str2 = "asd";
ByteArrayOutputStream os = new ByteArrayOutputStream();
os.write(str1.getBytes());
os.write(str2.getBytes());
byte[] byteArray = os.toByteArray();
System.out.println(new String(byteArray));
}
ByteArrayInputStream——byte数组截取
/**
* 从内存中读取字节数组
*/
public static void main(String[] args) throws IOException {
String str1 = "132asd";
byte[] b = new byte[3];
ByteArrayInputStream in = new ByteArrayInputStream(str1.getBytes());
in.read(b);
System.out.println(new String(b));
in.read(b);
System.out.println(new String(b));
}