# System.console()

public static void main(String[] args) {
		Console console = System.console();
		char[] pass = console.readPassword("Enter password:");
		String password = new String(pass);
	}

## What is the result?
A. A compilation error occurs at line n1.
B. A compilation error occurs at line n2.
C. The code reads the password without echoing characters on the console.
**D. A compilation error occurs because the IOException isn't declared to be thrown or caught?**
- [x] **Answer: D**

Console:

Exception in thread "main" java.lang.NullPointerException
	at exam.ocpjp.v1.q123.Test.main(Test.java:9)

:::warning
[參考網站](https://openhome.cc/Gossip/JavaGossip-V1/Console.htm)
要注意的是，以javaw所執行的應用程式（例如在使用Eclipse或NetBeans等IDE時），沒有主控台（Console），也就取不到Console物件，使用System.console()只會傳回null。
所以這題如果用Eclipse做, 只會得到NullPointerException
:::

###### tags: `ocpjp`