JavaLearning:IO

来源：互联网发布：最好用的纹身单片机编辑：程序博客网时间：2024/05/16 17:44

package org.fun.classdemo;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.io.OutputStream;public class OutputStreamDemo {public static void main(String[] args) throws IOException {File file = new File("d:" + File.separator + "demo.txt");OutputStream out = null;out = new FileOutputStream(file,true);String str = "hello wrold,JavaLearning!";byte b[] = str.getBytes();for (int i = 0; i < b.length; i++) {out.write(b[i]);}out.close();}}

package org.fun.classdemo;import java.io.File;import java.io.FileWriter;import java.io.IOException;import java.io.Writer;public class WriterDemo {public static void main(String[] args) throws IOException {File file = new File("d:" + File.separator + "demo.txt");Writer out = null;out = new FileWriter(file);String str = "hello wrold";out.write(str);out.close();}}

package org.fun.classdemo;import java.io.File;import java.io.FileInputStream;import java.io.IOException;import java.io.InputStream;public class InputStreamDemo {public static void main(String[] args) throws IOException {File file = new File("d:" + File.separator + "demo.txt");InputStream input = null;input = new FileInputStream(file);byte[] b = new byte[(int) file.length()];// 开辟空间接收读取的内容for (int i = 0; i < b.length; i++) {b[i] = (byte) input.read();// 一个个的读取数据}System.out.println(new String(b));input.close();}}

package org.fun.classdemo;import java.io.File;import java.io.FileReader;import java.io.IOException;import java.io.Reader;public class ReaderDemo {public static void main(String[] args) throws IOException {File file = new File("d:" + File.separator + "demo.txt");Reader input = null;input = new FileReader(file);char[] b = new char[(int) file.length()];// 开辟空间接收读取的内容for (int i = 0; i < b.length; i++) {b[i] = (char) input.read();// 一个个的读取数据}System.out.println(new String(b));input.close();}}

package org.fun.io;import java.io.File;import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.InputStream;import java.io.OutputStream;public class Copy {public static void main(String[] args) throws Exception {if (args.length != 2) {System.out.println("操作语法错误");System.out.println("ex:java Copy file1 file2");System.exit(1);}if(args[0].equals(args[1])){System.out.println("无法复制自身文件");System.exit(1);}File file1=new File(args[0]);if(file1.exists()){File file2=new File(args[1]);InputStream input=new FileInputStream(file1);OutputStream output=new FileOutputStream(file2);int temp=0;while((temp=input.read())!=-1){output.write(temp);}System.out.println("copy success");input.close();output.close();}else{System.out.println("源文件不存在");}}}

1 0