标签:des http io os ar java for sp 文件
1.文件和文件夹的创建
2.文件的读取
3.文件的写入
4.文件的复制(字符流、字节流、处理流)
5.以图片地址下载图片
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public static void NewFile(String pathString) { File file = new File(pathString); if (!file.exists()) { try { if (file.createNewFile()) { System.out.println( "文件创建成功" ); } } catch (Exception e) { // TODO: handle exception e.printStackTrace(); } } else { System.out.println( "文件已存在" ); } } |
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public static void NewFileBox(String pathString) { File file2 = new File(pathString); if (!file2.exists()) { if (file2.mkdirs()) { System.out.println( "文件夹成功" ); } } else { System.out.println( "文件夹存在" ); file2.delete(); //销毁文件 } } |
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public static void main(String[] args) { NewFile( "test/file.txt" ); NewFileBox( "test/a/a/a/a" ); } |
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public static void ForFileWriter(String string,String fileName) { File file = new File(fileName); try { FileWriter fWriter = new FileWriter(file); fWriter.write(string); fWriter.close(); } catch (Exception e) { // TODO: handle exception e.printStackTrace(); } } |
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public static void ForBufferedWriter(String string,String desFile) { BufferedWriter bWriter = null ; try { bWriter = new BufferedWriter( new FileWriter( new File(desFile))); bWriter.write(string.toString()); bWriter.close(); } catch (Exception e) { e.printStackTrace(); } } |
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public static void main(String[] args) { ForFileWriter( "用FileWriter写入文件" , "test/writer1.txt" ); ForBufferedWriter( "用BufferedWriter写入文件" , "test/writer2.txt" ); } |
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public static void testReadByReader(String fileName){ File file = new File(fileName); FileReader fis = null ; try { fis = new FileReader(file); char [] arr = new char [ 1024 * 1000 * 6 ]; int len = fis.read(arr); String data = new String(arr, 0 , len); fis.close(); System.out.println(fileName+ "中按FileReader读取的文件内容是:\n" +data); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } |
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public static void testReadByInputStream(String fileName){ File file = new File(fileName); FileInputStream fis = null ; try { fis = new FileInputStream(file); byte [] arr = new byte [ 1024 * 1000 * 6 ]; int len = fis.read(arr); String data = new String(arr, 0 , len); fis.close(); System.out.println(fileName+ "中按FileInputStream读取的文件内容是:\n" +data); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } |
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public static void testReadByBufferedReader(String fileName) { BufferedReader bReader = null ; String line = null ; StringBuffer buffer = new StringBuffer(); try { bReader = new BufferedReader( new FileReader( new File(fileName))); while ((line = bReader.readLine())!= null ) { buffer.append(line).append( "\n" ); } } catch (Exception e) { // TODO: handle exception e.printStackTrace(); } System.out.println(fileName+ "中按BufferedReader读取的文件内容是:\n" +buffer.toString()); } |
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public static void main(String[] args) { testReadByInputStream( "res/我.txt" ); testReadByReader( "res/我.txt" ); testReadByBufferedReader( "res/我.txt" ); } |
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public static void FileCopy1(String readfile,String writeFile) { try { FileReader input = new FileReader(readfile); FileWriter output = new FileWriter(writeFile); int read = input.read(); while ( read != - 1 ) { output.write(read); read = input.read(); } input.close(); output.close(); } catch (IOException e) { System.out.println(e); } } |
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public static void FileCopy2(String readfile,String writeFile) { try { FileInputStream input = new FileInputStream(readfile); FileOutputStream output = new FileOutputStream(writeFile); int read = input.read(); while ( read != - 1 ) { output.write(read); read = input.read(); } input.close(); output.close(); } catch (IOException e) { System.out.println(e); } } |
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public static void FileCopy3(String readfile,String writeFile) { BufferedReader bReader = null ; BufferedWriter bWriter = null ; String line = null ; try { bReader = new BufferedReader( new FileReader( new File(readfile))); bWriter = new BufferedWriter( new FileWriter( new File(writeFile))); while ((line = bReader.readLine())!= null ) { bWriter.write(line); bWriter.newLine(); } bWriter.close(); bReader.close(); } catch (Exception e) { // TODO: handle exception e.printStackTrace(); } } |
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public static void main(String[] args) { FileCopy1( "res/我.txt" , "test/1.txt" ); FileCopy2( "res/我.txt" , "test/2.txt" ); FileCopy3( "res/我.txt" , "test/3.txt" ); FileCopy2( "res/me.jpg" , "test/33.jpg" ); } |
标签:des http io os ar java for sp 文件
原文地址:http://www.cnblogs.com/91loveme/p/4063181.html