# By value
```java
int y = 3;
int z = y;
z++;
System.out.println("y: " + y);
System.out.println("z: " + z);
```
# By reference
```java
int [] a = {1,2,3};
int [] b = a;
b[1] = 5;
System.out.println("a[1]: " + a[1]);
System.out.println("b[1]: " + b[1]);
```