标签:ble void generated not io流 数组 int long 拷贝文件
package copyDemo; import java.io.FileNotFoundException; import java.io.FileReader; import java.io.FileWriter; import java.io.IOException; import java.io.Reader; import java.io.Writer; public class CopyDemo { public static void main(String[] args) { copy(); System.out.println("done"); } public static void copy() { Reader reader = null; Writer writer = null; try { //创建文件读取对象 reader = new FileReader("src/reader/Demo1.java"); //创建文件写入对象 writer = new FileWriter("Copy.java"); int num = -1; while((num=reader.read()) != -1) { writer.write(num); } } catch (FileNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); }catch(IOException e) { e.printStackTrace(); }finally { try { if(writer != null) { writer.close(); if(reader != null) { reader.close(); } } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } }
package copyDemo; import java.io.FileNotFoundException; import java.io.FileReader; import java.io.FileWriter; import java.io.IOException; import java.io.Reader; import java.io.Writer; public class CopyDemo2 { public static void main(String[] args) { copy(); System.out.println("done"); } public static void copy() { Reader reader = null; Writer writer = null; try { //创建文件读取对象 reader = new FileReader("src/reader/Demo1.java"); //创建文件写入对象 writer = new FileWriter("Copy.java"); int num = -1; char[] chs =new char[1024]; while((num=reader.read(chs)) != -1) { writer.write(chs,0,num); } } catch (FileNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); }catch(IOException e) { e.printStackTrace(); }finally { try { if(writer != null) { writer.close(); if(reader != null) { reader.close(); } } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } }
package copyDemo; import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.FileNotFoundException; import java.io.FileReader; import java.io.FileWriter; import java.io.Flushable; import java.io.IOException; import java.io.Reader; import java.io.Writer; public class CopyDemo3 { public static void main(String[] args) { copy(); System.out.println("done"); } public static void copy() { Reader reader = null; Writer writer = null; BufferedReader br = null; BufferedWriter bw = null; try { //创建文件读取对象 reader = new FileReader("src/reader/Demo1.java"); //创建文件写入对象 writer = new FileWriter("Copy1.java"); br = new BufferedReader(reader); bw = new BufferedWriter(writer); String line = null; while((line = br.readLine()) != null) { bw.write(line); bw.newLine(); } bw.flush(); } catch (FileNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); }catch(IOException e) { e.printStackTrace(); }finally { try { if(writer != null) { writer.close(); if(reader != null) { reader.close(); } } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } }
package copyDemo1; import java.io.BufferedInputStream; import java.io.BufferedOutputStream; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; public class Demo1 { public static void main(String[] args) { long start = System.currentTimeMillis(); copy3(); long end = System.currentTimeMillis(); System.out.println("耗时"+(end-start)+"毫秒"); /** * 总结: * 高效缓冲区再加上字节数组复制最快 * 不是高效缓冲区,但是有字节数组第二 * 高效缓冲区单个字符提取第三 * 不是高效缓冲区,单个字符提取最慢 * * */ } public static void copy() { InputStream in = null; OutputStream out = null; try { in = new FileInputStream("E:/1.chm"); out = new FileOutputStream("E:/新建文件夹/1.chm"); /** * !!!字符能做到的,字节肯定能做到。字节能做到的,字符不一定能做到 * 字节可以拷贝文件,电影,拷贝的时候只要文件名不错就基本上没啥问题 */ int len = -1; while((len=in.read()) != -1) { out.write(len); } out.flush(); } catch (FileNotFoundException e) { e.printStackTrace(); }catch (IOException e) { e.printStackTrace(); }finally { if(out != null) { try { out.close(); if(in != null) { in.close(); } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } } public static void copy1() { InputStream in = null; OutputStream out = null; try { in = new FileInputStream("E:/1.chm"); out = new FileOutputStream("E:/新建文件夹/1.chm"); /** * !!!字符能做到的,字节肯定能做到。字节能做到的,字符不一定能做到 * 字节可以拷贝文件,电影,拷贝的时候只要文件名不错就基本上没啥问题 */ int len = -1; byte[] chs = new byte[1024]; while((len=in.read(chs)) != -1) { out.write(chs, 0, len); } } catch (FileNotFoundException e) { e.printStackTrace(); }catch (IOException e) { e.printStackTrace(); }finally { if(out != null) { try { out.close(); if(in != null) { in.close(); } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } } public static void copy2() { InputStream in = null; OutputStream out = null; BufferedOutputStream bo = null; BufferedInputStream bp = null; try { in = new FileInputStream("E:/1.chm"); out = new FileOutputStream("E:/新建文件夹/1.chm"); bp = new BufferedInputStream(in); bo = new BufferedOutputStream(out); /** * !!!字符能做到的,字节肯定能做到。字节能做到的,字符不一定能做到 * 字节可以拷贝文件,电影,拷贝的时候只要文件名不错就基本上没啥问题 */ int len = -1; byte[] chs = new byte[1024]; while((len=bp.read(chs)) != -1) { bo.write(chs, 0, len); } bo.flush(); } catch (FileNotFoundException e) { e.printStackTrace(); }catch (IOException e) { e.printStackTrace(); }finally { if(out != null) { try { out.close(); if(in != null) { in.close(); } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } } public static void copy3() { InputStream in = null; OutputStream out = null; BufferedOutputStream bo = null; BufferedInputStream bp = null; try { in = new FileInputStream("E:/1.chm"); out = new FileOutputStream("E:/新建文件夹/1.chm"); bp = new BufferedInputStream(in); bo = new BufferedOutputStream(out); /** * !!!字符能做到的,字节肯定能做到。字节能做到的,字符不一定能做到 * 字节可以拷贝文件,电影,拷贝的时候只要文件名不错就基本上没啥问题 */ int len = -1; while((len=bp.read()) != -1) { bo.write(len); } bo.flush(); } catch (FileNotFoundException e) { e.printStackTrace(); }catch (IOException e) { e.printStackTrace(); }finally { if(out != null) { try { out.close(); if(in != null) { in.close(); } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } } }
标签:ble void generated not io流 数组 int long 拷贝文件
原文地址:https://www.cnblogs.com/java-jiangtao-home/p/9374978.html