如何通過java程序找到jar的最新jar版本？

Question

在我的項目中有40到50個jar文件可用，每次都需要很多時間才能找到每個jar的最新版本。你可以任何一個幫我爲這個寫一個java程序？

Answer 1

您可能只想使用maven：http://maven.apache.org/ 或其他依賴項管理器，如Ivy。

Answer 2

At the time of ant-build please call this method 
public void ExpungeDuplicates(String filePath) { 
    Map<String,Integer> replaceJarsMap = null; 
    File folder = null; 
    File[] listOfFiles = null; 
    List<String> jarList = new ArrayList<String>(); 
    String files = ""; 
    File deleteFile = null; 
    Iterator<String> mapItr = null; 
    //String extension ="jar"; 
    try { 
      folder = new File(filePath); 
     listOfFiles = folder.listFiles(); 
     for (int i = 0; i < listOfFiles.length; i++) { 
      if (listOfFiles[i].isFile()) { 
       files = listOfFiles[i].getName(); 
       jarList.add(files); 
      } 
     } 
     if (jarList.size() > 0) { 
      replaceJarsMap = PatternClassifier.findDuplicatesOrLowerVersion(jarList); 
      System.err.println("Duplicate/Lower Version - Total Count : "+replaceJarsMap.size()); 
      mapItr = replaceJarsMap.keySet().iterator(); 
      while (mapItr.hasNext()) { 
       String key = mapItr.next(); 
       int repeat = replaceJarsMap.get(key); 
       System.out.println(key +" : "+repeat); 
       for (int i = 0; i <repeat; i++) { 
        deleteFile = new File(filePath + System.getProperty ("file.separator")+key); 
        try{ 
        if (deleteFile != null && deleteFile.exists()){ 
         if(deleteFile.delete()){ 
          System.err.println(key +" deleted"); 
         } 
        } 
        }catch (Exception e) { 
        } 
       } 
      } 
     } 

} catch (Exception e) { 
    // TODO: handle exception 
} 
} 

您只需要將您的Lib的路徑給這個函數。此方法將查找所有重複或較低版本的文件。 下面給出了至關重要的功能......它從您提供的文件列表中找出重複項。

public static Map<String,Integer> findDuplicatesOrLowerVersion(List<String> fileNameList) { 
    List<String> oldJarList = new ArrayList<String>(); 
    String cmprTemp[] = null; 
    boolean match = false; 
    String regex = "",regexFileType = "",verInfo1 = "",verInfo2 = "",compareName = "",tempCompareName = "",tempJarName =""; 
    Map<String,Integer> duplicateEntryMap = new HashMap<String, Integer>(); 
    int count = 0; 
    Collections.sort(fileNameList, Collections.reverseOrder()); 
    try{ 
     int size = fileNameList.size(); 
     for(int i = 0;i<size;i++){ 
      cmprTemp = fileNameList.get(i).split("[0-9\\._]*"); 
      for(String s : cmprTemp){ 
       compareName += s; 
      } 
      regex = "^"+compareName+"[ajr0-9_\\-\\.]*"; 
      regexFileType = "[0-9a-zA-Z\\-\\._]*\\.jar$"; 
      if(fileNameList.get(i).matches(regexFileType) && !oldJarList.contains(fileNameList.get(i))){ 
       for(int j = i+1 ;j<size;j++){ 
        cmprTemp = fileNameList.get(j).split("[0-9\\._]*"); 
        for(String s : cmprTemp){ 
         tempCompareName += s; 
        } 
        match = (fileNameList.get(j).matches(regexFileType) && tempCompareName.matches(regex)); 
        if(match){ 
          cmprTemp = fileNameList.get(i).split("[a-zA-Z\\-\\._]*"); 
          for(String s : cmprTemp){ 
           verInfo1 += s; 
          } 
          verInfo1 += "000"; 
          cmprTemp = fileNameList.get(j).split("[a-zA-Z\\-\\._]*"); 
          for(String s : cmprTemp){ 
           verInfo2 += s; 
          } 
          verInfo2 += "000"; 
          int length = 0; 
          if(verInfo1.length()>verInfo2.length()){ 
           length = verInfo2.length();       
         }else{ 
          length = verInfo1.length(); 
         } 
         if(Long.parseLong(verInfo1.substring(0,length))>=Long.parseLong(verInfo2.substring(0,length))){ 
          count = 0; 
          if(!oldJarList.contains(fileNameList.get(j))){ 
           oldJarList.add(fileNameList.get(j)); 
           duplicateEntryMap.put(fileNameList.get(j),++count); 
          }else{ 
           count = duplicateEntryMap.get(fileNameList.get(j)); 
           duplicateEntryMap.put(fileNameList.get(j),++count); 
          } 
         }else{ 
          tempJarName = fileNameList.get(i); 
         } 
         match = false;verInfo1 = "";verInfo2 = ""; 
       } 
        tempCompareName = ""; 
       } 
       if(tempJarName!=null && !tempJarName.equals("")){ 
        count = 0; 
        if(!oldJarList.contains(fileNameList.get(i))){ 
         oldJarList.add(fileNameList.get(i)); 
         duplicateEntryMap.put(fileNameList.get(i),++count); 
        }else{ 
         count = dupl icateEntryMap.get(fileNameList.get(i)); 
         duplicateEntryMap.put(fileNameList.get(i),++count); 
        } 
        tempJarName = ""; 
       } 
      } 
      compareName = ""; 
     } 
    }catch (Exception e) { 
     e.printStackTrace(); 
    } 
    return duplicateEntryMap; 
}  

什麼findDuplicatesOrLowerVersion（名單fileNameList）函數的任務 - 只要它發現的重複和passting一個映射，其中包含的文件和時間數低版本重複的名字。

Try this. The remaining file exist in the folder should be latest or files with out duplicates.Am using this for finding the oldest files.on the basis of that it will find the old and delete it. 
This am only checking the name..Futher improvement you can made. 

Where PatternClassifier is a class which contains the second method given here.