如何使用 SuperCsv 隔离类的实例？答案

【问题标题】：How to isolate an instance of a class with SuperCsv?如何使用 SuperCsv 隔离类的实例？
【发布时间】：2014-08-11 13:51:08
【问题描述】：

实际上，我有一个 ArticleModele 类，我在其中存储 .csv 列的内容，但我不知道如何访问对应于 .csv 中特定行的类的特定实例。这是我的代码：

 public static ArticleModele readWithCsvDozerBeanReader() throws Exception {   
     final CellProcessor[] processors = new CellProcessor[] { 

     new Optional(),
     new Optional(),
     new Optional()

     };

     ICsvDozerBeanReader beanReader = null;
     try {
     beanReader = new CsvDozerBeanReader(new FileReader(CSV_FILENAME),   CsvPreference.EXCEL_NORTH_EUROPE_PREFERENCE);

     beanReader.getHeader(true); // ignore the header
     beanReader.configureBeanMapping(ArticleModele.class, FIELD_MAPPING);

     ArticleModele articleModele;
     while( (articleModele = beanReader.read(ArticleModele.class, processors)) != null )        {
     System.out.println(String.format(" %s", articleModele));}
     return articleModele;
     }
     finally {
     if( beanReader != null ) {
     beanReader.close();
      }
     }
    }
  }

这是课程：

public class ArticleModele {
    public String titre;
    public String contenu;
    public String attachement; 

    public ArticleModele(){}

    public ArticleModele(String titre, String contenu, String attachement){
    this.titre=titre;
    this.contenu=contenu;
    this.attachement=attachement;

    }
    public String getTitre(){
    return titre;
    }
    public void  setTitre(String titre){
    this.titre=titre;
    }
   public String getContenu(){
   return contenu;
  
   }
    public void setContenu(String contenu){
    this.contenu=contenu;
   }
    
    public String getAttachement(){
    return attachement;
      
      }
    public void setAttachement(String attachement){
    this.attachement=attachement;    
       }
    public String toString() {
    return String.format("ArticleModele [titre=%s, content=%s, attachement=%s]",      titre, contenu, attachement);
   }
}

【问题讨论】：

您可以返回一个列表并根据需要进行处理，而不是返回单个 ArticleModele 。您可以通过从该列表中获取所需的任何行实例来访问它。

标签： java csv dozer supercsv

【解决方案1】：

代码返回最后一个结果，因为它覆盖了articleModele。

ArticleModele articleModele;
while( (articleModele = beanReader.read(ArticleModele.class, processors))
        != null)             {
    System.out.println(articleModele);
}
return articleModele;

所以收集一份清单。

public static List<ArticleModele> readWithCsvDozerBeanReader() throws Exception { 
    List<ArticleModele> articleModele = new ArrayList<>();
    ArticleModele articleModele;
    while( (articleModele = beanReader.read(ArticleModele.class, processors))
         != null)             {
        System.out.println(articleModele);
        articleModeles.add(articleModele);
    }
    return articleModeles;

如果可行，您可以获得第 i^th 篇文章。并走文章：

for (ArticleModele articleModele : articleModeles) { ...

【讨论】：

【解决方案2】：

例如，如果你想按标题获取一行，你可以有这样的东西：

public static Map<String, ArticleModele> readWithCsvDozerBeanReader() throws Exception {   
     final CellProcessor[] processors = new CellProcessor[] { 

     new Optional(),
     new Optional(),
     new Optional()

     };
Map<String, ArticleModele> map = new HashMap<String,ArticleModele>();
     ICsvDozerBeanReader beanReader = null;
     try {
     beanReader = new CsvDozerBeanReader(new FileReader(CSV_FILENAME),   CsvPreference.EXCEL_NORTH_EUROPE_PREFERENCE);

     beanReader.getHeader(true); // ignore the header
     beanReader.configureBeanMapping(ArticleModele.class, FIELD_MAPPING);

     ArticleModele articleModele;
     while( (articleModele = beanReader.read(ArticleModele.class, processors)) != null )        {
     System.out.println(String.format(" %s", articleModele));}
     map.put(articleModele .getTitre(),articleModele);
     }
     finally {
     if( beanReader != null ) {
     beanReader.close();
      }
     }
    }

  }

并获取您想要使用的任何 articleModele：

map.get("titre");

【讨论】：