www.pudn.com > htmlsaver.rar > FileURLChange.java

import java.lang.*; 
import java.net.*; 
import java.io.*; 
 
/* give a base url, then change the file or path 
 */ 
public class FileURLChange 
{ 
  /* the base URL, a host or a directory */ 
  protected URL baseURL; 
  /* the base URL directory */ 
  protected URL baseDir; 
  /* the host name */ 
  protected String host; 
  /* the base file's  */ 
  protected URL fileURL; 
   
  public FileURLChange(String url) throws UnknowFileURL 
  { 
    try { 
      baseURL = new URL(url); 
    } 
    catch (MalformedURLException e) { 
      System.err.println("URL ERROR"); 
      throw new UnknowFileURL(); 
    } 
     
    host = baseURL.getHost(); 
    if (baseURL.getQuery() != null) 
    { 
      System.err.println("Query ERROR"); 
      throw new UnknowFileURL(); 
    } 
     
    String fileName = getBaseFile(baseURL); 
    if (fileName == null) 
    { 
      System.err.println("file URL Error"); 
      throw new UnknowFileURL(); 
    } 
    else 
    { 
      try { 
        fileURL = new URL(fileName); 
      } 
      catch (MalformedURLException e) 
      { 
        System.err.println("file URL Error"); 
        throw new UnknowFileURL(); 
      } 
    } 
     
    try { 
      baseDir = new URL(getFileDir(fileURL.toString())); 
    } 
    catch (MalformedURLException e) { 
      System.err.println("URL ERROR"); 
      throw new UnknowFileURL(); 
    } 
  } 
   
  public FileURLChange(String url, String base) throws UnknowFileURL 
  { 
    try { 
      baseURL = new URL(url); 
      baseDir = new URL(base); 
    } 
    catch (MalformedURLException e) { 
      System.err.println("Base URL ERROR"); 
      throw new UnknowFileURL(); 
    } 
     
    host = baseURL.getHost(); 
    if (baseURL.getQuery() != null) 
    { 
      System.err.println("Query ERROR"); 
      throw new UnknowFileURL(); 
    } 
     
    String fileName = getBaseFile(baseURL); 
    if (fileName == null) 
    { 
      System.err.println("file URL Error"); 
      throw new UnknowFileURL(); 
    } 
    else 
    { 
      try { 
        fileURL = new URL(fileName); 
      } 
      catch (MalformedURLException e) 
      { 
        System.err.println("file URL Error"); 
        throw new UnknowFileURL(); 
      } 
    } 
  } 
   
  public boolean setBase(String base) 
  { 
    try { 
      baseURL = new URL(base); 
    } 
    catch (MalformedURLException e) { 
      return false; 
    } 
    return true; 
  } 
   
  /* get the base file name */ 
  public static String getBaseFile(URL url) 
  { 
    String prot = url.getProtocol(); 
    if (prot.equals("http")) 
    { 
      return getHttpBaseFile(url); 
    } 
    else 
    { 
      System.err.println("http ERROR:" + url.toString()); 
      return null; 
    } 
  } 
   
  public static String getHttpBaseFile(URL url) 
  { 
    String file = url.getProtocol() + "://"; 
     
    String tmp = url.getUserInfo(); 
    if (tmp != null) 
      file = file.concat(tmp + "@"); 
       
    file = file.concat(url.getHost()); 
     
    int port = url.getPort(); 
    if (port != -1) 
      file = file.concat(":" + port); 
     
    file = file.concat(url.getPath()); 
     
    return file; 
  } 
   
  public String getBaseDir() 
  { 
    return baseDir.toString(); 
  } 
   
  public static String getFileDir(String file) 
  { 
    String dir = file.substring(0, file.lastIndexOf('/')+1); 
    return dir; 
  } 
   
  public String getRelativeFile(String relURL) 
  { 
    URL url; 
    try { 
      url = new URL(baseDir, relURL); 
    } 
    catch (MalformedURLException e) { 
      return relURL; 
    } 
    /* 
    String s = getBaseFile(url); 
    if (s != null) 
      return s; 
    else 
      return relURL; 
    */ 
    return url.toString(); 
  } 
   
  public static String getAutoName(String url) 
  { 
    URL u; 
    try { 
      u = new URL(url); 
    } 
    catch (MalformedURLException e) { 
      return null; 
    } 
     
    String s = getBaseFile(u); 
    if (s == null) 
      return null; 
    return s.substring(s.lastIndexOf('/')+1); 
  } 
   
  public String getDirOfAbsoluteFile(String absURL, boolean sameDir) 
  { 
    if (sameDir == true) 
      return ""; 
       
    URL url; 
    try { 
      url = new URL(absURL); 
    } 
    catch (MalformedURLException e) { 
      return null; 
    } 
     
    if (url.getQuery() != null) 
      return null; 
       
    String newDir = getBaseFile(url); 
    newDir = getFileDir(newDir); 
    String[] newDirs = newDir.split("/"); 
     
    String dir = baseDir.toString(); 
    String[] dirs = dir.split("/"); 
     
    if (newDirs.length < dirs.length) 
      return ""; 
     
    int i; 
    for (i = 0; i < dirs.length; i++) 
      if (!newDirs[i].equals(dirs[i])) 
        return ""; 
         
    String path = new String(); 
    for (i = dirs.length; i < newDirs.length; i++) 
    { 
      path += newDirs[i] + "/"; 
    } 
     
    return path; 
  } 
   
  public String getDirOfRelativeFile(String relURL, boolean sameDir) 
  { 
    if (sameDir == true) 
      return ""; 
       
    URL url; 
    try { 
      url = new URL(baseDir, relURL); 
    } 
    catch (MalformedURLException e) { 
      return null; 
    } 
     
    String newDir = getBaseFile(url); 
    newDir = getFileDir(newDir); 
    String[] newDirs = newDir.split("/"); 
     
    String dir = baseDir.toString(); 
    String[] dirs = dir.split("/"); 
     
    int i; 
    String path = new String(); 
    for (i = dirs.length; i < newDirs.length; i++) 
    { 
      path += newDirs[i] + "/"; 
    } 
     
    return path; 
  } 
   
  public static void main(String[] args) 
  { 
    SystemIn in = new SystemIn(); 
         
    System.out.print("Please input a URL:"); 
    String url = in.readLine(); 
     
    FileURLChange base; 
    try { 
      base = new FileURLChange(url); 
    } 
    catch (UnknowFileURL e) { 
      System.err.println("Error!"); 
      return; 
    } 
     
    System.out.println(base.fileURL); 
    System.out.println(base.getFileDir(base.fileURL.toString())); 
     
    System.out.print("Please input a relative URL:"); 
    System.out.println(base.getRelativeFile(in.readLine())); 
  } 
}