用字符流讀取文件的幾種方法

public class Demo2 {
	public static void main(String[] args) {
		//fileReader1();//創建字符數組，將文件字符流讀入數組，用for each循環進行遍歷輸出
		//fileReader2();//讀取文件字符流挨個獲取輸出
		//fileReader3();//創建字符數組把字符讀進數組，獲取長度添加進字符串緩衝區，最後將字符串輸出
		fileReader4();//建立字符串緩衝區，把文件讀進逐行流，賦值給字符串，當字符串不爲空時，將獲取的字符串添加進緩衝區，
	}

	private static void fileReader4() {
		// 使用逐行流
		StringBuffer sb=new StringBuffer();
		FileReader fr;
		try {
			fr = new FileReader("c:\\ffff.txt");
			BufferedReader br=new BufferedReader(fr);
			String str=br.readLine();
			while(str!=null)
			{
				sb.append(str);
				str=br.readLine();
			}
			System.out.println(sb);
			br.close();
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
		
		
		
	}

	private static void fileReader3() {
		// TODO Auto-generated method stub
		StringBuffer sb=new StringBuffer();
		try {
			FileReader fr=new FileReader("c:\\ffff.txt");
			char[] ch=new char[1024];
			int i=fr.read(ch);
			while(i!=-1)
			{
				sb.append(new String(ch));
				i=fr.read();
			}
			System.out.println(sb);
			fr.close();
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
		
	}

	private static void fileReader2() {
		// TODO Auto-generated method stub
		try {
			FileReader fr=new FileReader("c:\\ffff.txt");
			int i=fr.read();
			while(i!=-1)
			{
				System.out.print((char)i);
				i=fr.read();
			}
			fr.close();
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
	}

	private static void fileReader1() {
		// TODO Auto-generated method stub
		try {
			FileReader fr=new FileReader("c:\\ffff.txt");
			char[] ch=new char[100];
			 fr.read(ch);
			 for(char c:ch)
			 {
				 System.out.print(c);
			 }
			 fr.close();
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
		
	}

}