action="#{languageFrom.showChoice}": Target

package yingServlet;?


import javax.faces.bean.ManagedBean; ?//记得不是import javax.annotation.ManagedBean; ?? @ManagedBean? public class LanguageForm { private String language ; public String getLanguage() { return language; } public void setLanguage(String language) { this.language = language.trim() ; ?? } ? public String showChoice() {? if (isMissing(language)) {? return "missing-language" ;? }? else if (language.equalsIgnoreCase("Java") || language.equalsIgnoreCase("Groovy")) {? return "good-language" ;? }? else {? return "bad-language" ;? } }? private boolean isMissing(String value) {? return (value == null) || value.trim().isEmpty() ;? } }