J学 74 -27 -83 -90 ?utf-8?
```java
package com.string;
public class CNStrTest {
public static void main(String[] args) {
String str = "J学";
byte[] b = str.getBytes();
for (int i = 0; i < b.length; i++) {
System.out.print(b[i] + " ");
}
}
}
```
结果
```
74 -27 -83 -90
```