线程“主”java.lang.NoClassDefFoundError 中的异常：org/apache/commons/codec/DecoderException

Posted 2023-02-16

【中文标题】线程“主”java.lang.NoClassDefFoundError 中的异常：org/apache/commons/codec/DecoderException

【英文标题】：Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/codec/DecoderException

【发布时间】：2013-03-19 02:36:36

【问题描述】：

我尝试通过 Solrj 查询 Solr

这是我的代码

public class ReadFromSolr 

public static void main(String[] args) throws MalformedURLException, SolrServerException 

     String url = "http://localhost:8983/solr";
      try
     SolrServer server = new CommonsHttpSolrServer(url);
     ModifiableSolrParams params = new ModifiableSolrParams();
       params.set("qt", "/select");
        params.set("q", "name");

            QueryResponse response = server.query(params);

            System.out.println("response = " + response);

      

         catch (MalformedURLException ex) 
            ex.printStackTrace();
         
      catch (SolrServerException ex) 
            ex.printStackTrace();
         

它给了我一个例外

PS。我的项目中有以下罐子：

**apache - 公共日志记录， *httpclient -4.2 , httpcore 4.2.1, slf4j - api 1.6.2， apache - solr - solrj -1.4.0***

 Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/codec/DecoderException
        at org.apache.commons.httpclient.HttpMethodBase.<init>(HttpMethodBase.java:220)
        at org.apache.commons.httpclient.methods.GetMethod.<init>(GetMethod.java:89)
        at org.apache.solr.client.solrj.impl.CommonsHttpSolrServer.request(CommonsHttpSolrServer.java:288)
        at org.apache.solr.client.solrj.impl.CommonsHttpSolrServer.request(CommonsHttpSolrServer.java:243)
        at org.apache.solr.client.solrj.request.QueryRequest.process(QueryRequest.java:89)
        at org.apache.solr.client.solrj.SolrServer.query(SolrServer.java:118)
        at com.gismo.ReadFromSolr.main(ReadFromSolr.java:27)
    Caused by: java.lang.ClassNotFoundException: org.apache.commons.codec.DecoderException
        at java.net.URLClassLoader$1.run(Unknown Source)
        at java.net.URLClassLoader$1.run(Unknown Source)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)

【参考方案1】：

你需要在类路径上commons-codec.jar。