apach nutch中线程“main”java.lang.NoClassDefFoundError异常

Question

线程“main”java.lang.noClassDeffounderror：bin/crawl中出现异常，原因是：java.net.urlClassLoader$1.java.net.urlClassLoader.AccessController.doprivileged（本机方法）在java.net.urlClassLoader.findClass(urlClassLoader.java:205)在java.net.urlClassLoader.java:205)在java.lang.ClassLoader.loadClass(classLoader.java:323)在程序将退出。

我能有个答案吗。

Answer 1

它不存在名为'bin/crawl'的命令。如果执行./bin/nutch，您将得到命令列表：

Usage: nutch COMMAND
 where COMMAND is one of:
 inject         inject new urls into the database
 hostinject     creates or updates an existing host table from a text file
 generate       generate new batches to fetch from crawl db
 fetch          fetch URLs marked during generate
 parse          parse URLs marked during fetch
 updatedb       update web table after parsing
 updatehostdb   update host table after parsing
 readdb         read/dump records from page database
 readhostdb     display entries from the hostDB
 index          run the plugin-based indexer on parsed batches
 elasticindex   run the elasticsearch indexer - DEPRECATED use the index command instead
 solrindex      run the solr indexer on parsed batches - DEPRECATED use the index command instead
 solrdedup      remove duplicates from solr
 solrclean      remove HTTP 301 and 404 documents from solr - DEPRECATED use the clean command instead
 clean          remove HTTP 301 and 404 documents and duplicates from     indexing backends configured via plugins
 parsechecker   check the parser for a given url
 indexchecker   check the indexing filters for a given url
 plugin         load a plugin and run one of its classes main()
 nutchserver    run a (local) Nutch server on a user defined port
 webapp         run a local Nutch web application
 junit          runs the given JUnit test
 or
 CLASSNAME  run the class named CLASSNAME
Most commands print help when invoked w/o parameters.

由于'bin/crawl'命令不存在，它假定它是一个类名，因此出现错误。

过去存在./bin/nutch crawl（不推荐使用），但现在有了一个特定的抓取脚本。使用此：

./bin/crawl