Java 读取文件

由于项目的需要，需要写一个解析文件的类。

 

import java.io.EOFException;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.net.URL;
import java.util.Hashtable;

import com.nokia.mms.*;

/**
 * 
 * @author JavaAlpha 解析用户发送的自定义文件，生成原始内容文件
 */

public class SeedAudit
{
 MMMessage mms  = new MMMessage();
 MMDecoder decoder = new MMDecoder();
 MMContent content = new MMContent();

 public SeedAudit(String file)
 {
  // 将MMS文件写到byte数组中
  byte[] mmsFile = readFile(file);
  // 将数组set到content中
  content.setContent(mmsFile, 0, mmsFile.length);
  
  decoder.setMessage(mmsFile); 
  
  try
  {
   decoder.decodeMessage();
   mms = decoder.getMessage();
   storeContents(mms);
  } catch (IOException e)
  {
   // TODO Auto-generated catch block
   e.printStackTrace();
  } catch (MMDecoderException e)
  {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
  
  
  /*// 获取MMS文件的id
  String id = content.getContentId();
  // 获取MMS文件的type
  String type = content.getType();
  // 获取MMS文件长度
  int length = content.getLength();

  System.out.println("id--" + id);
  System.out.println("type--" + type);

  for (int i = 0; i < length; i++)
  {
   try
   {
    if (type.compareTo(IMMConstants.CT_TEXT_PLAIN) == 0)
    {
     // 如果文件类型是文本文件
     content.saveToFile(id + ".txt");
    } else if (type.compareTo(IMMConstants.CT_IMAGE_JPEG) == 0)
    {
     // 如果文件类型是jpg文件
     content.saveToFile(id + ".jpg");
    } else if (type.compareTo(IMMConstants.CT_IMAGE_GIF) == 0)
    {
     // 如果文件类型是gif文件
     content.saveToFile(id + ".gif");
    } else
    {
     content.saveToFile(id);
    }
   } catch (IOException e)
   {
    e.printStackTrace();
   }
  }*/
 }

 private void storeContents(MMMessage mm) throws IOException
 {
  MMContent mmContent = null;
  String path = getPath();

  for (int j = 0; j < mm.getNumContents(); j++)
  {
   mmContent = mm.getContent(j);
   
   /*System.out.println(" Content " + j + " --> ID = "
     + mmContent.getContentId() + ", TYPE = "
     + mmContent.getType() + ", LENGTH = "
     + mmContent.getLength());*/

   if ((mmContent.getType()).compareTo(IMMConstants.CT_IMAGE_WBMP) == 0)
    mmContent.saveToFile(path
      + cleanString(mmContent.getContentId()) + ".wbmp");
   else if ((mmContent.getType())
     .compareTo(IMMConstants.CT_TEXT_PLAIN) == 0)
    mmContent.saveToFile(path
      + cleanString(mmContent.getContentId()) + ".txt");
   else if ((mmContent.getType())
     .compareTo(IMMConstants.CT_APPLICATION_SMIL) == 0)
    mmContent.saveToFile(path
      + cleanString(mmContent.getContentId()) + ".smil");
   else if ((mmContent.getType())
     .compareTo(IMMConstants.CT_IMAGE_JPEG) == 0)
    mmContent.saveToFile(path
      + cleanString(mmContent.getContentId()) + ".jpg");
   else if ((mmContent.getType()).compareTo(IMMConstants.CT_IMAGE_GIF) == 0)
    mmContent.saveToFile(path
      + cleanString(mmContent.getContentId()) + ".gif");
   else if ((mmContent.getType()).compareTo("audio/wav") == 0)
    mmContent.saveToFile(path
      + cleanString(mmContent.getContentId()) + ".wav");
   else
    mmContent.saveToFile(path
      + cleanString(mmContent.getContentId()));
  }
 }

 private String cleanString(String str)
 {
  String result;

  if ((str.charAt(0) == '<') && (str.charAt(str.length() - 1) == '>'))
   result = str.substring(1, str.length() - 1);
  else
   result = str;
  return result;
 }

 private String getPath()
 {
  URL url = getClass().getResource(getClass().getName() + ".class");
  String classPath = url.getHost() + url.getFile();
  int pos = classPath.lastIndexOf("/");
  return classPath.substring(0, pos + 1);
 }

 // 读取文件
 private byte[] readFile(String filename)
 {
  int fileSize = 0;
  RandomAccessFile fileH = null;

  // Opens the file for reading.
  try
  {
   fileH = new RandomAccessFile(filename, "r");
   fileSize = (int) fileH.length();
  } catch (IOException ioErr)
  {
   System.err.println("Cannot find " + filename);
   System.err.println(ioErr);
   System.exit(200);
  }

  // allocates the buffer large enough to hold entire file
  byte[] buf = new byte[fileSize];

  // reads all bytes of file
  int i = 0;
  try
  {
   while (true)
   {
    try
    {
     buf[i++] = fileH.readByte();
    } catch (EOFException e)
    {
     break;
    }
   }
  } catch (IOException ioErr)
  {
   System.out.println("ERROR in reading of file" + filename);
  }

  return buf;
 }

 public static void main(String[] args)
 {
  SeedAudit seed = new SeedAudit("e:/Sample.mms");
 }
}