//创建文件  public static boolean createFile(File file, boolean deleteOnExists) throws IOException {                   if ( file . exists ()) {                           if ( deleteOnExists ){                                   deleteFile ( file );                           } else {                                   return true ;                           }                   }           File parent = file . getParentFile ();           if ( parent != null && ! parent . exists ()) {                   parent . mkdirs ();           }           return file . createNewFile ();       }       //删除文件     public static boolean deleteFile ( File path ) {                   boolean result = true ;                   if ( path . exists ()) {                           if ( path . isDirectory ()) {                                   File [] files = path . listFiles ();                                   for ( int i = 0 , count = files . length ; i < count ; i ++) {                                           result &= deleteFile ( files [ i ]);                                   }                                   result &= path . delete (); // Delete empty directory.                           } else {                                   result &= path . delete ();                           }                           return result ;                   } else {                           return false ;                   }          }  //删除文件夹内文件  public static boolean deleteInternalFilr ( File path ){           boolean result = true ;           if ( path . exists ()){                if ( path . isDirectory ()){                    File [] files = path . listFiles ();                    for ( int i = 0 , count = files . length ; i < count ; i ++) {                            result &= deleteFile ( files [ i ]);                        }                    }                }                return result ;          }  //安装文件  public static boolean installFile ( File path , Activity context ){           boolean result = true ;           try {                Intent intent = new Intent ( Intent . ACTION_VIEW );                intent . setDataAndType ( Uri . fromFile ( path ), "application/vnd.android.package-archive" );                context . startActivityForResult ( intent , 1 );           } catch ( Exception ex ){                ex . printStackTrace ();                result = false ;           }                return result ;           }           //复制文件 public static boolean copyFile ( String savePath , String sourcePath ){                   try {                           FileInputStream fis = new FileInputStream ( new File ( sourcePath ));                           FileOutputStream fos = new FileOutputStream ( new File ( savePath ));                                                    byte [] temp = new byte [ 1024 ];                                                    int ch ;                           while (( ch = fis . read ( temp ))!=- 1 ){                                   fos . write ( temp , 0 , ch );                           }                                            } catch ( Exception e ){                           e . printStackTrace ();                           return false ;                   }                   return true ;           }