IO编程基础(二)

CopyFile

package org.wp.io;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

public class CopyFile {
	public static void main(String args[]) {
		try {
			FileInputStream fis = new FileInputStream("F:\\test.jpg");
			FileOutputStream fos = new FileOutputStream("F:\\temp.jpg");
			// 返回读取文件的内容转换为int形式
			int read = fis.read();
			while (read != -1) {
				fos.write(read);
				read = fis.read();
			}
			fis.close();
			fos.close();
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}

		try {
			FileInputStream inStream = new FileInputStream("F:/test.jpg");
			FileOutputStream outStream = new FileOutputStream(
					"F:/temporary.jpg");
			byte[] buffer = new byte[1024];
			// 返回实际读取到文件内容的长度
			int length = inStream.read(buffer);
			while (length != -1) {
				// 如果不指定写入的文件长度,文件大小会超出复制的文件
				outStream.write(buffer, 0, length);
				length = inStream.read(buffer);
			}
			inStream.close();
			outStream.close();
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}

		try {
			FileInputStream fileInputStream = new FileInputStream("F:/test.jpg");
			FileOutputStream fileOutputStream = new FileOutputStream(
					"F:/occasional .jpg");
			byte[] buffer = new byte[1024];
			// 设置每次读取的长度
			int length = fileInputStream.read(buffer, 0, 20);
			while (length != -1) {
				// 设置每次写入的长度
				fileOutputStream.write(buffer, 0, 20);
				length = fileInputStream.read(buffer, 0, 20);
			}
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
}

 

ReaderWriterTest

package org.wp.io;

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

public class ReaderWriterTest {
	public static void main(String arg[]) {
		try {
			FileReader fr = new FileReader("F:/test.txt");
			FileWriter fw = new FileWriter("F:/temp.txt");
			int read = fr.read();
			while (read != -1) {
				fw.write(read);
				read = fr.read();
			}
			fr.close();
			fw.close();
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
}

 

BufferedReaderWriterTest

package org.wp.io;

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

public class BufferedReaderWriterTest {
	public static void main(String args[]) {
		try {
			FileReader fr = new FileReader("F:/test.txt");
			BufferedReader br = new BufferedReader(fr);
			FileWriter fw = new FileWriter("F:/temp.txt");
			BufferedWriter bw = new BufferedWriter(fw);

			// 读取一行的内容,但不包含换行符
			String str = br.readLine();
			while (str != null) {
				bw.write(str);
				// 换行
				bw.newLine();
				str = br.readLine();
			}

			br.close();
			bw.close();
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}

		try {
			FileReader fileReader = new FileReader("F:/test.txt");
			// BufferedReader(Reader in, int sz)
			// 创建一个使用指定大小输入缓冲区的缓冲字符输入流
			BufferedReader bufferedReader = new BufferedReader(fileReader, 1024);

			FileWriter fileWriter = new FileWriter("F:/temporary.txt");
			// BufferedWriter(Writer out, int sz)
			// 创建一个使用给定大小输出缓冲区的新缓冲字符输出流
			BufferedWriter bufferedWriter = new BufferedWriter(fileWriter, 1024);

			String s = bufferedReader.readLine();
			while (s != null) {
				bufferedWriter.write(s);
				bufferedWriter.newLine();
				s = bufferedReader.readLine();
			}

			bufferedReader.close();
			bufferedWriter.close();
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
}

 

InputStreamReaderOutputStreamWriterTest

package org.wp.io;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;

public class InputStreamReaderOutputStreamWriterTest {
	public static void main(String args[]) {
		try {
			FileInputStream fis = new FileInputStream("F:/test.txt");
			// 默认为操作系统的字符编码
			// 可以设置使用的字符编码
			// isr = new InputStreamReader(fis, "UTF-8");
			InputStreamReader isr = new InputStreamReader(fis);
			BufferedReader br = new BufferedReader(isr);

			FileOutputStream fos = new FileOutputStream("F:/temp.txt");
			// 默认为操作系统的字符编码
			// 可以设置使用的字符编码
			// isw = new OutputStreamWriter(fos, "UTF-8");
			OutputStreamWriter isw = new OutputStreamWriter(fos);
			BufferedWriter bw = new BufferedWriter(isw);

			String str = br.readLine();
			while (str != null) {
				bw.write(str);
				bw.newLine();
				str = br.readLine();
			}
			br.close();
			bw.close();
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
}

 

PrintStreamWriterTest

package org.wp.io;

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintStream;
import java.io.PrintWriter;

/**
 * PrintStream的方法不抛出IOException 只能封装OutputStream类型的字节流
 * 
 * PrintWriter的方法不抛出IOException 既可以封装OutputStream类型的字节流,也可以封装Writer类型的字符输出流
 * 
 * @author wp
 * 
 */
public class PrintStreamWriterTest {
	public static void main(String args[]) {
		try {
			FileInputStream fis = new FileInputStream("F:/test.txt");
			BufferedReader br = new BufferedReader(new InputStreamReader(fis));
			FileOutputStream fos = new FileOutputStream("F:/temp.txt");
			PrintStream ps = new PrintStream(fos);

			String str = br.readLine();
			while (str != null) {
				ps.println(str);
				str = br.readLine();
			}
			br.close();
			ps.close();
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}

		try {
			BufferedReader bufferedReader = new BufferedReader(
					new InputStreamReader(new FileInputStream("F:/test.txt")));
			FileWriter fw = new FileWriter("F:/temporary.txt");
			PrintWriter pw = new PrintWriter(fw);

			String s = bufferedReader.readLine();
			while (s != null) {
				pw.println(s);
				s = bufferedReader.readLine();
			}
			bufferedReader.close();
			pw.close();
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
}

 

DataInputOutputTest

package org.wp.io;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

/**
 * DataInputStream能够以一种与机器无关的方式,直接从底层字节输入流读取Java基本类型和String类型的数据
 * 
 * DataOutputStream能够直接将Java基本类型和String类型的数据写出到其他的字节输出流
 * 
 * @author wp
 * 
 */
public class DataInputOutputTest {
	public static void main(String args[]) {
		try {
			FileOutputStream fos = new FileOutputStream("F:/myfile.data");
			DataOutputStream dos = new DataOutputStream(fos);
			dos.writeUTF("麦迪");
			dos.writeInt(50);
			dos.close();

			FileInputStream fis = new FileInputStream("F:/myfile.data");
			DataInputStream dis = new DataInputStream(fis);
			System.out.println(dis.readUTF());
			System.out.println(dis.readInt());
			dis.close();
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
}

 

CharArrayReaderTest

package org.wp.io;

import java.io.CharArrayReader;
import java.io.IOException;
import java.io.Reader;

public class CharArrayReaderTest {
	public static void main(String args[]) {
		char[] b = { 'I', ' ', 'a', 'm', ' ', 'S', 'a', 'i', 'l', 'i', 'n',
				'g', '!' };
		CharArrayReader car = new CharArrayReader(b);
		new MyReader().getInfo(car);
	}
}

class MyReader {
	public void getInfo(Reader reader) {
		try {
			int read = reader.read();
			while (read != -1) {
				System.out.print((char) read);
				read = reader.read();
			}
			System.out.println();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
}

 

CharArrayWriterTest

package org.wp.io;

import java.io.CharArrayWriter;
import java.io.FileReader;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Date;

public class CharArrayWriterTest {
	public static void main(String args[]) {
		try {
			FileReader fr = new FileReader("F:/ooo.txt");
			int i = fr.read();
			while (i != -1) {
				System.out.println((char) i);
				i = fr.read();
			}
		} catch (IOException e) {
			CharArrayWriter caw = new CharArrayWriter();
			// true指定追加方式
			PrintWriter pw = new PrintWriter(caw, true);
			e.printStackTrace(pw);
			String info = caw.toString();
			Date time = new Date();
			// 可以将time和info信息写入数据库
			System.out.println("出错时间:" + time);
			System.out.println("错误信息:\n" + info);
		}
	}
}