通过ByteArrayOutputStream将inputStream转变为outputStream
通过ByteArrayOutputStream将inputStream转变为outputStream
?
?
1.首先，先编写一个获取文件输入流的方法 ops()。
2. 之后在调用此方法获得输入流，并通过 castToBAOStream(Object obj,int bufferSize)进行转化。
3.最后，写出 转化成功的 输出流。
?
?
?
·········10········20········30········40········50········60········70········80········90········100·······110·······120·······130·······140·······150
?
public class Stream { public static final int StreamFlushBufferSzie=100;//buffer size= 1K public static ByteArrayOutputStream castToBAOStream(Object obj,int bufferSize){ // Log logger = LogFactory.getLog(CommonUtil.class); ByteArrayOutputStream baos=new ByteArrayOutputStream(); if(obj.getClass().isInstance(baos)){ return (ByteArrayOutputStream)obj; }else{ InputStream fis; try{ fis=(FileInputStream)obj; try{ BufferedInputStream bis=new BufferedInputStream(fis); baos=new ByteArrayOutputStream(); BufferedOutputStream bos=new BufferedOutputStream(baos); int ch; int i=0; while((ch=bis.read())!=-1){ bos.write(ch); if(i++==bufferSize){ bos.flush(); i=0; } } bos.flush(); //提交文件流，很关键 bis.close(); return baos; }catch(ClassCastException e){ // logger.info("Stream object not a ByteArrayOutputStream or a FileInputStream:",e); return null; }catch(Exception e){ // logger.info("baos is null:",e); return null; } }catch(ClassCastException e){ fis=(InflaterInputStream)obj; try{ baos=new ByteArrayOutputStream(); BufferedOutputStream bos=new BufferedOutputStream(baos); int ch; int i=0; // ii.read(b, off, len) byte[] by = new byte[2048]; while((ch=fis.read(by))!=-1){ bos.write(by,0,ch); if(i++==bufferSize){ bos.flush(); i=0; } } bos.flush(); //提交文件流，很关键 fis.close(); // ZipUtil.getZipName().close(); return baos; }catch(ClassCastException e1){ // logger.info("Stream object not a ByteArrayOutputStream or a FileInputStream:",e1); return null; }catch(Exception e1){ // logger.info("baos is null:",e1); return null; } } } } //产生一个文件输入流 public static InputStream ops() throws FileNotFoundException { File file = new File("d://lin.txt"); FileInputStream fileInputStream = new FileInputStream(file); return fileInputStream; } public static void main(String[] args) throws IOException { try { // OutputStream outputStream = ops(); InputStream inputStream = ops(); ByteArrayOutputStream baos = castToBAOStream(inputStream,StreamFlushBufferSzie); InputStream is = new ByteArrayInputStream(baos.toByteArray()); File file=new File("d://new.txt"); FileOutputStream outb=new FileOutputStream(file); int bytesRead; byte[] buf = new byte[4 * 1024]; while((bytesRead = is.read(buf))!=-1){ outb.write(buf,0,bytesRead); } outb.flush(); outb.close(); is.close(); System.out.println(inputStream); } catch (FileNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } ?
?
?