java判断文件编码

/**                                                                             
* 获得远程URL文件的编码格式                                                    
*/                                                                             
public static String getReomoteURLFileEncode(URL url) {                         
   CodepageDetectorProxy detector = CodepageDetectorProxy.getInstance();         
   detector.add(new ParsingDetector(false));                                     
   detector.add(JChardetFacade.getInstance());                                   
   detector.add(ASCIIDetector.getInstance());                                    
   detector.add(UnicodeDetector.getInstance());                                  
   java.nio.charset.Charset charset = null;                                      
   try {                                                                         
    System.out.println(url);                                                    
    charset = detector.detectCodepage(url);                                     
   } catch (Exception ex) {                                                      
    ex.printStackTrace();                                                       
   }                                                                             
   if (charset != null) {                                                        
    return charset.name();                                                      
   } else {                                                                      
    return "utf-8";                                                             
   }                                                                             
}                                                                               
                                                                                 
                                                                                 
/**                                                                             
* 获得文件流的编码格式                                                         
*/                                                                             
public static String getInputStreamEncode(InputStream is) {                     
   CodepageDetectorProxy detector = CodepageDetectorProxy.getInstance();         
   detector.add(new ParsingDetector(false));                                     
   detector.add(JChardetFacade.getInstance());                                   
   detector.add(ASCIIDetector.getInstance());                                    
   detector.add(UnicodeDetector.getInstance());                                  
   java.nio.charset.Charset charset = null;                                      
   try {                                                                         
    charset = detector.detectCodepage(is, 0);                                   
   } catch (Exception ex) {                                                      
    ex.printStackTrace();                                                       
   }                                                                             
   if (charset != null) {                                                        
    return charset.name();                                                      
   } else {                                                                      
    return "utf-8";                                                             
   }                                                                             
}                                                                               
                                                                                 
/**                                                                             
* 获得本地文件的编码格式                                                       
*/                                                                             
public static String getLocalteFileEncode(String filePath) {                    
   CodepageDetectorProxy detector = CodepageDetectorProxy.getInstance();         
   detector.add(new ParsingDetector(false));                                     
   detector.add(JChardetFacade.getInstance());                                   
   detector.add(ASCIIDetector.getInstance());                                    
   detector.add(UnicodeDetector.getInstance());                                  
   java.nio.charset.Charset charset = null;                                      
   File file = new File(filePath);                                               
   try {                                                                         
    charset = detector.detectCodepage(file.toURI().toURL());                    
   } catch (Exception ex) {                                                      
    ex.printStackTrace();                                                       
   }                                                                             
   if (charset != null) {                                                        
    return charset.name();                                                      
   } else {                                                                      
    return "utf-8";                                                             
   }                                                                             
}                                                                               
/**                                                                             
* 获得字符串的编码格式                                                         
*/                                                                             
public static String getStringEncode(String str) {                              
   CodepageDetectorProxy detector = CodepageDetectorProxy.getInstance();         
   detector.add(new ParsingDetector(false));                                     
   detector.add(JChardetFacade.getInstance());                                   
   detector.add(ASCIIDetector.getInstance());                                    
   detector.add(UnicodeDetector.getInstance());                                  
   java.nio.charset.Charset charset = null;                                      
   InputStream myIn=new ByteArrayInputStream(str.getBytes());                    
   try {                                                                         
    charset = detector.detectCodepage(myIn,3);                                  
   } catch (Exception ex) {                                                      
    ex.printStackTrace();                                                       
   }                                                                             
   if (charset != null) {                                                        
    return charset.name();                                                      
   } else {                                                                      
    return "utf-8";                                                             
   }                                                                             
}