File f =new File("~"); //创建源 InputStream is =new FileInputStream(f); //选择流 is.read() 读取单个数据,并使游标下移 //操作(读取) is.close() //释放资源,输入流读取后必须释放资源

public class test{

public static void main(String[]args) 
{
	//创建源
	File f=new File("C:/Users/10853/eclipse-workspace/hell/src/hell/abc");
	InputStream is =null;//提升is的作用域,避免在try中声明后,作用域
						//只在try,finally中语句无法执行
	//选择流
	try {
		 is =new FileInputStream(f);
	//操作(读取)	
		int temp;
		while((temp=is.read())!=-1) //temp=is.read()表达式整体的值就是temp的值
		{							//is.read()会读取单个数据,当数据读取完毕时,返回-1
			System.out.println((char)temp);
		}
		
		
	} catch (FileNotFoundException e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	} catch (IOException e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	}finally
	{
		try {
			if(null!=is)//当is创建成功时才执行关闭
			{
				is.close();
			}
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	

} 
}