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struts2类型转换+校验

發布時間：2024/4/17 编程问答 48 豆豆

生活随笔收集整理的這篇文章主要介紹了 struts2类型转换+校验小編覺得挺不錯的,現在分享給大家,幫大家做個參考.

http://383984216-qq-com.iteye.com/blog/1151938

1.action中validate()與validateXxx()

用于action執行前的校驗，如果校驗失敗，跳到input視圖，
前者校驗整個Action；
后者校驗該Action中的Xxx方法.
如果兩者都有，則validateXxx方法會先調用。

2.struts2中輸入校驗的流程

a.類型轉換器將用戶請求字符串的參數轉化為java類型，并將其設為Action的屬性值。
b.如果轉換過程中出現異常，異常將保存在ActionContext中，conversionError攔截器負責將其封裝到fieldError中，否則直接到c,類型轉換完畢。
c.通過反射調用validateXxx()，然后調用validate()。
d.如果上面3步沒有出現fieldError,則調用action的處理請求方法,否則跳到input視圖.

3.struts2校驗框架

校驗配置文件的DTD在xword-core-2.2.3.jar中，系統自帶的校驗器的xml配置文件是
xword-core-2.2.3.jar里的com.opensymphony.xword2.vilidator.validators.default.xml文件

校驗配置文件名稱必須為
ActionClassName-validation.xml:Action類名-validation.xml
ActionClassName-ActoinAliasName-validation.xml:Action類名-類別名-validation.xml
類別名為在struts.xml中action的name屬性名。

如果要輸出國際化信息，則使用<message key="資源文件鍵名">或<message>${getText("資源文件鍵名")</message>

以上是服務器校驗，如果需要客戶端校驗，可以在提供了服務器校驗的基礎上，在<s:form>中添加validation="true"屬性，這樣，客戶端會根據服務端校驗框架自動生產客戶端的javascript語句，但不是所有的系統自帶校驗器都支持生成客戶端校驗腳本。

注：如果配置的自帶的校驗器不支持生成客戶端腳本，而客戶端form又設置了validation="true",那么將會報錯：

Java代碼 ?

Method?public?java.util.List?org.apache.struts2.components.Form.getValidators(java.lang.String)?threw?an?exception?when?invoked?on?org.apache.struts2.components.Form@5810af??

The?problematic?instruction: ??

---------- ??

==>?list?tag.getValidators("${tagName}")?as?validator?[on?line?46,?column?9?in?template/xhtml/form-close-validate.ftl] ??

?in?include?"/${parameters.templateDir}/xhtml/form-close-validate.ftl"?[on?line?25,?column?1?in?template/xhtml/form-close.ftl] ??

---------- ??

Java?backtrace?for?programmers: ??

---------- ??

freemarker.template.TemplateModelException:?Method?public?java.util.List?org.apache.struts2.components.Form.getValidators(java.lang.String)?threw?an?exception?when?invoked?on?org.apache.struts2.components.Form@5810af??

????at?freemarker.ext.beans.SimpleMethodModel.exec(SimpleMethodModel.java:130) ??

????at?freemarker.core.MethodCall._getAsTemplateModel(MethodCall.java:93) ??

????at?freemarker.core.Expression.getAsTemplateModel(Expression.java:89) ??

????at?freemarker.core.IteratorBlock.accept(IteratorBlock.java:94) ??

????at?freemarker.core.Environment.visit(Environment.java:210) ??

????at?freemarker.core.IteratorBlock$Context.runLoop(IteratorBlock.java:167) ??

????at?freemarker.core.Environment.visit(Environment.java:417) ??

????at?freemarker.core.IteratorBlock.accept(IteratorBlock.java:102) ??

????at?freemarker.core.Environment.visit(Environment.java:210) ??

????at?freemarker.core.MixedContent.accept(MixedContent.java:92) ??

????at?freemarker.core.Environment.visit(Environment.java:210) ??

????at?freemarker.core.ConditionalBlock.accept(ConditionalBlock.java:79) ??

????at?freemarker.core.Environment.visit(Environment.java:210) ??

????at?freemarker.core.MixedContent.accept(MixedContent.java:92) ??

????at?freemarker.core.Environment.visit(Environment.java:210) ??

????at?freemarker.core.Environment.include(Environment.java:1483) ??

????at?freemarker.core.Include.accept(Include.java:169) ??

????at?freemarker.core.Environment.visit(Environment.java:210) ??

????at?freemarker.core.MixedContent.accept(MixedContent.java:92) ??

????at?freemarker.core.Environment.visit(Environment.java:210) ??

????at?freemarker.core.Environment.process(Environment.java:190) ??

????at?freemarker.template.Template.process(Template.java:237) ??

????at?org.apache.struts2.components.template.FreemarkerTemplateEngine.renderTemplate(FreemarkerTemplateEngine.java:157) ??

????at?org.apache.struts2.components.UIBean.mergeTemplate(UIBean.java:559) ??

????at?org.apache.struts2.components.UIBean.end(UIBean.java:513) ??

????at?org.apache.struts2.views.jsp.ComponentTagSupport.doEndTag(ComponentTagSupport.java:42) ??

????at?org.apache.jsp.index_jsp._jspx_meth_s_005fform_005f0(index_jsp.java:226) ??

????at?org.apache.jsp.index_jsp._jspService(index_jsp.java:103) ??

????at?org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) ??

????at?javax.servlet.http.HttpServlet.service(HttpServlet.java:803) ??

????at?org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:384) ??

????at?org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320) ??

????at?org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266) ??

????at?javax.servlet.http.HttpServlet.service(HttpServlet.java:803) ??

????at?org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) ??

????at?org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) ??

????at?org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:88) ??

????at?org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) ??

????at?org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) ??

????at?org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:228) ??

????at?org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175) ??

????at?org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128) ??

????at?org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104) ??

????at?org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) ??

????at?org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:216) ??

????at?org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844) ??

????at?org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:634) ??

????at?org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:445) ??

????at?java.lang.Thread.run(Thread.java:619) ??

Caused?by:?java.lang.NullPointerException ??

????at?com.opensymphony.xwork2.validator.AnnotationActionValidatorManager.buildValidatorKey(AnnotationActionValidatorManager.java:219) ??

????at?com.opensymphony.xwork2.validator.AnnotationActionValidatorManager.getValidators(AnnotationActionValidatorManager.java:76) ??

????at?com.opensymphony.xwork2.validator.AnnotationActionValidatorManager.getValidators(AnnotationActionValidatorManager.java:72) ??

????at?org.apache.struts2.components.Form.getValidators(Form.java:265) ??

????at?sun.reflect.NativeMethodAccessorImpl.invoke0(Native?Method) ??

????at?sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) ??

????at?sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) ??

????at?java.lang.reflect.Method.invoke(Method.java:597) ??

????at?freemarker.ext.beans.BeansWrapper.invokeMethod(BeansWrapper.java:840) ??

????at?freemarker.ext.beans.SimpleMethodModel.exec(SimpleMethodModel.java:106) ??

????...?48?more ??

2011-8-18?0:17:17?org.apache.catalina.core.StandardWrapperValve?invoke ??

嚴重:?Servlet.service()?for?servlet?jsp?threw?exception ??

java.lang.NullPointerException ??