Executing a Block
A block is executed by executing its declarations and statements in sequence.
Executing a declaration creates a variable. When control leaves the block, the variable goes out of existence.
program text runtime storage
int a = readInt(); � a[_]
int b = readInt(); � a[_] b[_]
int temp = a; � a[_] b[_] temp[_]
a = b; � a[_] b[_] temp[_]
b = temp; � a[_] b[_] temp[_]
System.out.println(a); � a[_] b[_]
System.out.println(b); � a[_] b[_]