XStream xStream = new XStream(); 报错

严重: Servlet.service() for servlet [springMVC] in context with path [] threw exception [Handler processing failed; nested exception is java.lang.NoClassDefFoundError: com/thoughtworks/xstream/XStream] with root cause

java.lang.ClassNotFoundException: com.thoughtworks.xstream.XStream

at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1858)

at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1701)