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public static void main(String[] args) {
		try(FileOutputStream fos=new FileOutputStream("C:\\users\\kitchen\\desktop\\abc\\abc.txt");
				BufferedOutputStream bos=new BufferedOutputStream(fos);) {
		bos.write("我把数据写入到内部缓冲区中".getBytes());
//		bos.flush();
//		bos.close();
		//上面这几步不用再写，因为在jdk1.7中，自动刷新flush关闭close()
	} catch (Exception e) {
		e.printStackTrace();
	}
		
}

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public static void main(String[] args) {
		try(FileInputStream fis=new FileInputStream("C:\\users\\kitchen\\desktop\\abc\\abc.txt");
				BufferedInputStream bis=new BufferedInputStream(fis);) {
			int len=0;
			byte[] b=new byte[1024];
			while((len=bis.read(b))!=-1) {
				System.out.println(new String(b,0,len));
			}
		} catch (Exception e) {
			e.printStackTrace();// TODO: handle exception
		}
}

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public class Demo03Effectiveness {
	public static void main(String[] args) {
		//不使用字节缓冲流，277M文件复制11889毫秒
		long beginTime=System.currentTimeMillis();
		try(FileOutputStream fos=new FileOutputStream("C:\\Users\\kitchen\\Desktop\\abc\\copy.exe");
				FileInputStream fis=new FileInputStream("C:\\Users\\kitchen\\Desktop\\PhpStorm-2019.2.5.exe")) {
			byte[] b=new byte[1024];
			int len=0;
			while((len=fis.read(b))!=-1) {
				fos.write(b, 0, len);
			}
			
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			System.out.println("复制过程总共历时"+(System.currentTimeMillis()-beginTime)+"毫秒");
		}
    }
}

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public class Demo03Effectiveness {
	public static void main(String[] args) {
		//使用字节缓冲流,277M文件复制1433毫秒
		try(BufferedOutputStream bos=new BufferedOutputStream(new FileOutputStream("C:\\Users\\kitchen\\Desktop\\abc\\copy.exe"));
				BufferedInputStream bis=new BufferedInputStream(new FileInputStream("C:\\Users\\kitchen\\Desktop\\PhpStorm-2019.2.5.exe"))) {
			int len=0;
			byte[] b=new byte[1024];
			while((len=bis.read(b))!=-1) {
				bos.write(b, 0, len);
			}
		} catch (Exception e) {
			e.printStackTrace();
		}finally {
			System.out.println("复制过程总共历时"+(System.currentTimeMillis()-beginTime)+"毫秒");
		}
    }
}

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public class Demo03Effectiveness {
	public static void main(String[] args) {
		//使用字节缓冲流,277M文件复制480毫秒
		try(BufferedOutputStream bos=new BufferedOutputStream(new FileOutputStream("C:\\Users\\kitchen\\Desktop\\abc\\copy.exe"));
				BufferedInputStream bis=new BufferedInputStream(new FileInputStream("C:\\Users\\kitchen\\Desktop\\PhpStorm-2019.2.5.exe"))) {
			int len=0;
			byte[] b=new byte[1024*100];
			while((len=bis.read(b))!=-1) {
				bos.write(b, 0, len);
			}
		} catch (Exception e) {
			e.printStackTrace();
		}finally {
			System.out.println("复制过程总共历时"+(System.currentTimeMillis()-beginTime)+"毫秒");
		}
    }
}

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public class Demo04BufferedWriter {
	public static void main(String[] args) {
		try(BufferedWriter bw=new BufferedWriter(new FileWriter("src\\demo36\\abc.txt"))){
			for(int i=0;i<10;i++) {
				bw.write("我是你爸爸，嘎嘎嘎");
				bw.newLine();
			}
		}catch (Exception e) {
			e.printStackTrace();
		}
	}
}

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public class Demo05BufferedReader {
	public static void main(String[] args) {
		try(BufferedReader br=new BufferedReader(new FileReader("src\\demo36\\abc.txt"));){
//			String line="";
//			while((line=br.readLine())!=null) {
//				System.out.println(line);
//			}
			
			int len=0;
			char[] b=new char[10];
			while((len=br.read(b))!=-1) {
				System.out.println(new String(b,0,len));
			}
		}catch(IOException e) {
			e.printStackTrace();
		}
	}
}

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public class BufferedReaderDemo {
    public static void main(String[] args) throws IOException {
      	 // 创建流对象
        BufferedReader br = new BufferedReader(new FileReader("in.txt"));
		// 定义字符串,保存读取的一行文字
        String line  = null;
      	// 循环读取,读取到最后返回null
        while ((line = br.readLine())!=null) {
            System.out.print(line);
            System.out.println("------");
        }
		// 释放资源
        br.close();
    }
}

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public class BufferedWriterDemo throws IOException {
  public static void main(String[] args) throws IOException  {
    	// 创建流对象
  	BufferedWriter bw = new BufferedWriter(new FileWriter("out.txt"));
    	// 写出数据
      bw.write("我是");
    	// 写出换行
      bw.newLine();
      bw.write("你");
      bw.newLine();
      bw.write("爸爸");
      bw.newLine();
  	// 释放资源
      bw.close();
  }
}
输出效果:
我是
你
爸爸

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9

3.侍中、侍郎郭攸之、费祎、董允等，此皆良实，志虑忠纯，是以先帝简拔以遗陛下。愚以为宫中之事，事无大小，悉以咨之，然后施行，必得裨补阙漏，有所广益。
8.愿陛下托臣以讨贼兴复之效，不效，则治臣之罪，以告先帝之灵。若无兴德之言，则责攸之、祎、允等之慢，以彰其咎；陛下亦宜自谋，以咨诹善道，察纳雅言，深追先帝遗诏，臣不胜受恩感激。
4.将军向宠，性行淑均，晓畅军事，试用之于昔日，先帝称之曰能，是以众议举宠为督。愚以为营中之事，悉以咨之，必能使行阵和睦，优劣得所。
2.宫中府中，俱为一体，陟罚臧否，不宜异同。若有作奸犯科及为忠善者，宜付有司论其刑赏，以昭陛下平明之理，不宜偏私，使内外异法也。
1.先帝创业未半而中道崩殂，今天下三分，益州疲弊，此诚危急存亡之秋也。然侍卫之臣不懈于内，忠志之士忘身于外者，盖追先帝之殊遇，欲报之于陛下也。诚宜开张圣听，以光先帝遗德，恢弘志士之气，不宜妄自菲薄，引喻失义，以塞忠谏之路也。
9.今当远离，临表涕零，不知所言。
6.臣本布衣，躬耕于南阳，苟全性命于乱世，不求闻达于诸侯。先帝不以臣卑鄙，猥自枉屈，三顾臣于草庐之中，咨臣以当世之事，由是感激，遂许先帝以驱驰。后值倾覆，受任于败军之际，奉命于危难之间，尔来二十有一年矣。
7.先帝知臣谨慎，故临崩寄臣以大事也。受命以来，夙夜忧叹，恐付托不效，以伤先帝之明，故五月渡泸，深入不毛。今南方已定，兵甲已足，当奖率三军，北定中原，庶竭驽钝，攘除奸凶，兴复汉室，还于旧都。此臣所以报先帝而忠陛下之职分也。至于斟酌损益，进尽忠言，则攸之、祎、允之任也。
5.亲贤臣，远小人，此先汉所以兴隆也；亲小人，远贤臣，此后汉所以倾颓也。先帝在时，每与臣论此事，未尝不叹息痛恨于桓、灵也。侍中、尚书、长史、参军，此悉贞良死节之臣，愿陛下亲之信之，则汉室之隆，可计日而待也。

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public class Demo05TextSort {
	public static void main(String[] args) {
		Map<String,String> map=new HashMap<String,String>();
		try(BufferedReader br=new BufferedReader(new FileReader("src\\demo36\\text.txt"));
				BufferedWriter bw=new BufferedWriter(new FileWriter("src\\demo36\\textSort.txt"))){
			String s="";
			while((s=br.readLine())!=null) {
				String[] arr=s.split("\\.");
				map.put(arr[0], arr[1]);
			}
			for(String key:map.keySet()) {
				bw.write(key+"."+map.get(key));
				bw.newLine();
			}
			
		}catch(IOException e){
			e.printStackTrace();
		}
	}
}

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public class ReaderDemo {
    public static void main(String[] args) throws IOException {
        FileReader fileReader = new FileReader("E:\\File_GBK.txt");
        int read;
        while ((read = fileReader.read()) != -1) {
            System.out.print((char)read);
        }
        fileReader.close();
    }
}
输出结果：
���

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InputStreamReader isr = new InputStreamReader(new FileInputStream("in.txt"));
InputStreamReader isr2 = new InputStreamReader(new FileInputStream("in.txt") , "GBK");

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public class ReaderDemo2 {
    public static void main(String[] args) throws IOException {
      	// 定义文件路径,文件为gbk编码
        String FileName = "E:\\file_gbk.txt";
      	// 创建流对象,默认UTF8编码
        InputStreamReader isr = new InputStreamReader(new FileInputStream(FileName));
      	// 创建流对象,指定GBK编码
        InputStreamReader isr2 = new InputStreamReader(new FileInputStream(FileName) , "GBK");
		// 定义变量,保存字符
        int read;
      	// 使用默认编码字符流读取,乱码
        while ((read = isr.read()) != -1) {
            System.out.print((char)read); // ��Һ�
        }
        isr.close();
      
      	// 使用指定编码字符流读取,正常解析
        while ((read = isr2.read()) != -1) {
            System.out.print((char)read);// 大家好
        }
        isr2.close();
    }
}

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OutputStreamWriter isr = new OutputStreamWriter(new FileOutputStream("out.txt"));
OutputStreamWriter isr2 = new OutputStreamWriter(new FileOutputStream("out.txt") , "GBK");

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public class OutputDemo {
    public static void main(String[] args) throws IOException {
      	// 定义文件路径
        String FileName = "E:\\out.txt";
      	// 创建流对象,默认UTF8编码
        OutputStreamWriter osw = new OutputStreamWriter(new FileOutputStream(FileName));
        // 写出数据
      	osw.write("你好"); // 保存为6个字节
        osw.close();
      	
		// 定义文件路径
		String FileName2 = "E:\\out2.txt";
     	// 创建流对象,指定GBK编码
        OutputStreamWriter osw2 = new OutputStreamWriter(new FileOutputStream(FileName2),"GBK");
        // 写出数据
      	osw2.write("你好");// 保存为4个字节
        osw2.close();
    }
}

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public class TransDemo {
   public static void main(String[] args) {      
    	// 1.定义文件路径
     	String srcFile = "file_gbk.txt";
        String destFile = "file_utf8.txt";
		// 2.创建流对象
    	// 2.1 转换输入流,指定GBK编码
        InputStreamReader isr = new InputStreamReader(new FileInputStream(srcFile) , "GBK");
    	// 2.2 转换输出流,默认utf8编码
        OutputStreamWriter osw = new OutputStreamWriter(new FileOutputStream(destFile));
		// 3.读写数据
    	// 3.1 定义数组
        char[] cbuf = new char[1024];
    	// 3.2 定义长度
        int len;
    	// 3.3 循环读取
        while ((len = isr.read(cbuf))!=-1) {
            // 循环写出
          	osw.write(cbuf,0,len);
        }
    	// 4.释放资源
        osw.close();
        isr.close();
  	}
}

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FileOutputStream fileOut = new FileOutputStream("employee.txt");
ObjectOutputStream out = new ObjectOutputStream(fileOut);

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public class Employee implements java.io.Serializable {
    public String name;
    public String address;
    public transient int age; // transient瞬态修饰成员,不会被序列化
    public void addressCheck() {
      	System.out.println("Address  check : " + name + " -- " + address);
    }
}

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public class SerializeDemo{
   	public static void main(String [] args)   {
    	Employee e = new Employee();
    	e.name = "zhangsan";
    	e.address = "beiqinglu";
    	e.age = 20; 
    	try {
      		// 创建序列化流对象
          ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream("employee.txt"));
        	// 写出对象
        	out.writeObject(e);
        	// 释放资源
        	out.close();
        	fileOut.close();
        	System.out.println("Serialized data is saved"); // 姓名，地址被序列化，年龄没有被序列化。
        } catch(IOException i)   {
            i.printStackTrace();
        }
   	}
}
输出结果：
Serialized data is saved

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public class DeserializeDemo {
   public static void main(String [] args)   {
        Employee e = null;
        try {		
             // 创建反序列化流
             FileInputStream fileIn = new FileInputStream("employee.txt");
             ObjectInputStream in = new ObjectInputStream(fileIn);
             // 读取一个对象
             e = (Employee) in.readObject();
             // 释放资源
             in.close();
             fileIn.close();
        }catch(IOException i) {
             // 捕获其他异常
             i.printStackTrace();
             return;
        }catch(ClassNotFoundException c)  {
        	// 捕获类找不到异常
             System.out.println("Employee class not found");
             c.printStackTrace();
             return;
        }
        // 无异常,直接打印输出
        System.out.println("Name: " + e.name);	// zhangsan
        System.out.println("Address: " + e.address); // beiqinglu
        System.out.println("age: " + e.age); // 0
    }
}

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public class Employee implements java.io.Serializable {
     // 加入序列版本号
     private static final long serialVersionUID = 1L;
     public String name;
     public String address;
     // 添加新的属性 ,重新编译, 可以反序列化,该属性赋为默认值.
     public int eid; 

     public void addressCheck() {
         System.out.println("Address  check : " + name + " -- " + address);
     }
}

1

static final long serialVersionUID=42L;

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public class Demo07Practice {
	public static void main(String[] args) {
		write();
		read();
	}

	public static void write() {
		ArrayList<Person> list = new ArrayList<Person>();
		list.add(new Person("水月儿", 18));
		list.add(new Person("邱若水", 19));
		list.add(new Person("水冰儿", 20));
		try (ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("src\\demo37\\demo07.txt"))) {
			oos.writeObject(list);
		} catch (IOException e) {
			e.printStackTrace();
		}
		System.out.println("success");
	}

	public static void read() {
		ArrayList<Person> list = new ArrayList<Person>();
		try (ObjectInputStream ois = new ObjectInputStream(new FileInputStream("src\\demo37\\demo07.txt"))) {
			list = (ArrayList<Person>) ois.readObject();
			for (Person p : list) {
				System.out.println(p.getName() + " " + p.getAge());
			}
		} catch (IOException e) {
			e.printStackTrace();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
}

1

PrintStream ps = new PrintStream("ps.txt")；

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public class Demo09PrintStream {
	public static void main(String[] args) throws FileNotFoundException {
		System.out.println("我是在控制台输出的");
		
		PrintStream ps=new PrintStream("src\\demo37\\demo09.txt");
		System.setOut(ps);
		System.out.println("我是在文件中输出的");
		ps.close();
	}
}