IO流實作檔案複制

使用位元組流實作檔案讀寫：

@Test
	public void copy() throws IOException{
		File inFile = new File("D:\\workspace\\VideoShow\\WebRoot\\assets\\ffefg.mp4");
		File outFile = new File("C:\\Users\\admin\\Desktop\\test1.mp4");
		if(!inFile.exists()){
			System.err.println("檔案不存在");
		}else{
			if(!inFile.isFile()){
				System.err.println("該檔案是檔案夾");
			}else{
				FileInputStream is = new FileInputStream(inFile);
				FileOutputStream os = new FileOutputStream(outFile);
				int r;
				long start=System.currentTimeMillis();
				while((r=is.read())!=-1){
					os.write(r);
					os.flush();
				}
				long end=System.currentTimeMillis();
				if(null!=os){
					os.close();
				}
				if(null!=is){
					is.close();
				}
				System.err.println(end-start);
			}
		}
	}
           

使用buffer實作讀寫：

@Test
	public void copyByBuffer() throws IOException{
		File inFile = new File("D:\\workspace\\VideoShow\\WebRoot\\assets\\ffefg.mp4");
		File outFile = new File("C:\\Users\\admin\\Desktop\\test1.mp4");
		if(!inFile.exists()){
			System.err.println("檔案不存在");
		}else{
			if(!inFile.isFile()){
				System.err.println("該檔案是檔案夾");
			}else{
				FileInputStream is = new FileInputStream(inFile);
				BufferedInputStream bis=new BufferedInputStream(is);
				FileOutputStream os = new FileOutputStream(outFile);
				BufferedOutputStream bos = new BufferedOutputStream(os);
				int r;
				long start=System.currentTimeMillis();
				while((r=bis.read())!=-1){
					bos.write(r);
					bos.flush();
				}
				long end=System.currentTimeMillis();
				if(null!=bos){
					bos.close();
				}
				if(null!=os){
					os.close();
				}
				if(null!=bis){
					bis.close();
				}
				if(null!=is){
					is.close();
				}
				System.err.println(end-start);
			}
		}
	}
           

使用數組緩沖讀寫位元組流：

@Test
	public void copyByArrayBuffer() throws IOException{
		File inFile = new File("D:\\workspace\\VideoShow\\WebRoot\\assets\\ffefg.mp4");
		File outFile = new File("C:\\Users\\admin\\Desktop\\test1.mp4");
		if(!inFile.exists()){
			System.err.println("檔案不存在");
		}else{
			if(!inFile.isFile()){
				System.err.println("該檔案是檔案夾");
			}else{
				FileInputStream is = new FileInputStream(inFile);
				FileOutputStream os = new FileOutputStream(outFile);
				byte[] arr=new byte[1024];
				int r;
				long start=System.currentTimeMillis();
				while((r=is.read(arr,0,arr.length))!=-1){
					os.write(arr,0,r);
					os.flush();
				}
				long end=System.currentTimeMillis();
				if(null!=os){
					os.close();
				}
				if(null!=is){
					is.close();
				}
				System.err.println(end-start);
			}
		}
	}
           

使用IOUtils實作檔案複制：

@Test
	public void copyByIOUtils() throws FileNotFoundException, IOException{
		File inFile = new File("D:\\workspace\\VideoShow\\WebRoot\\assets\\ffefg.mp4");
		File outFile = new File("C:\\Users\\admin\\Desktop\\test1.mp4");
		if(!inFile.exists()){
			System.err.println("檔案不存在");
		}else{
			if(!inFile.isFile()){
				System.err.println("該檔案是檔案夾");
			}else{
				long start=System.currentTimeMillis();
				IOUtils.copy(new FileInputStream(inFile), new FileOutputStream(outFile));
				long end1=System.currentTimeMillis();
				System.err.println(end1-start);
			}
		}
	}