public FileReader(String fileName)
           throws FileNotFoundException

public FileReader(File file)
           throws FileNotFoundException

public int read()
         throws IOException

package java19;

import java.io.FileReader;
import java.io.IOException;

/**
 * 2017/10/12
 * 说明：
 */
public class FileReaderDemo {
    public static void main(String[] args) {
        FileReader fr = null;
        try {
            fr = new FileReader("demo.txt");

            int ch = 0;
            while((ch = fr.read()) != -1){
                System.out.print((char)ch);
            }
        }catch (IOException e){
            e.printStackTrace();
        }finally {
            if(fr != null){
                try {
                    fr.close();
                } catch (IOException e) {
                    e.printStackTrace();
                    throw new RuntimeException("流关闭失败"+e.getMessage());
                }

            }
        }


    }
}

public int read(char[] cbuf)
         throws IOException

package java19;

import java.io.FileReader;
import java.io.IOException;

/**
 * 2017/10/12
 * 说明：
 */
public class FileReaderDemo {
    public static void main(String[] args) {
        FileReader fr = null;
        try {
            fr = new FileReader("demo.txt");
            char[] chs = new char[1024];

            int length = 0;
            while((length = fr.read(chs)) != -1){
                System.out.print(new String(chs,0,length));
            }
        }catch (IOException e){
            e.printStackTrace();
        }finally {
            if(fr != null){
                try {
                    fr.close();
                } catch (IOException e) {
                    e.printStackTrace();
                    throw new RuntimeException("流关闭失败"+e.getMessage());
                }

            }
        }


    }
}

package java19;

import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

/**
 * 2017/10/12
 * 说明：
 */
public class FileCopy {
    public static void main(String[] args) throws IOException {
        //创建输入流和输出流
        FileReader fr = new FileReader("demo.txt");
        FileWriter fw = new FileWriter("test1.txt");

        //文件复制
        int ch = 0;
        while((ch = fr.read()) != -1){
            fw.write(ch);
        }



        //关闭流
        fr.close();
        fw.close();



    }
}

package java19;

import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

/**
 * 2017/10/12
 * 说明：
 */
public class FileCopy {
    public static void main(String[] args) throws IOException {
        //创建输入流和输出流
        FileReader fr = new FileReader("demo.txt");
        FileWriter fw = new FileWriter("test2.txt");

        //文件复制
        char[] buffer = new char[1024];
        int len = 0 ;
        while((len = fr.read(buffer) )!= -1){
            fw.write(buffer,0,len);
        }

        //关闭流
        fr.close();
        fw.close();



    }
}