升级到 Java 1.8 会导致问题

Question

我正在尝试将在 1.6 上运行的当前 java 项目升级到 1.8，但程序编译得很好，但是当我去 http://localhost:8080/MyProject/login.jsp- 时出现错误。

我正在使用 eclipse luna，我将 java_HOME 更改为 1.8，将 eclipse 项目方面更改为 1.8，并更新了 javax.servlet-api=3.1.0。

堆栈跟踪

springframework.web.util.NestedServletException: Request processing failed; nested exception is org.apache.tiles.impl.CannotRenderException: ServletException including path '/WEB-INF/jsp/template/noLayout.jsp'.
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:943) ~[spring-webmvc-4.0.0.RELEASE.jar:4.0.0.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:822) ~[spring-webmvc-4.0.0.RELEASE.jar:4.0.0.RELEASE]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:735) ~[servlet-api-3.0.jar:na]
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:807) ~[spri

Caused by: org.apache.tiles.impl.CannotRenderException: ServletException including path '/WEB-INF/jsp/template/noLayout.jsp'.
at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:692) ~[tiles-core-2.2.2.jar:2.2.2]
at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:644) ~[tiles-core-2.2.2.jar:2.2.2]
at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:627) ~[tiles-core-2.2.2.jar:2.2.2]
at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:321) ~[tiles-core-2.2.2.jar:2.2.2]
at org.springframework.web.servlet.view.tiles2.TilesView.renderMergedOutputModel(TilesView.java:88) ~[spring-webmvc-4.0.0.RELEASE.jar:4.0.0.RELEASE]
at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:266) ~[spring-webmvc-4.0.0.RELEASE.jar:4.0.0.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1225) ~[spring-webmvc-4.0.0.RELEASE.jar:4.0.0.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1012) ~[spring-webmvc-4.0.0.RELEASE.jar:4.0.0.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959) ~[spring-webmvc-4.0.0.RELEASE.jar:4.0.0.RELEASE]
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:876) ~[spring-webmvc-4.0.0.RELEASE.jar:4.0.0.RELEASE]
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:931) ~[spring-webmvc-4.0.0.RELEASE.jar:4.0.0.RELEASE]
... 65 common frames omitted
Caused by: org.apache.tiles.util.TilesIOException: ServletException including path '/WEB-INF/jsp/template/noLayout.jsp'.
at org.apache.tiles.servlet.context.ServletUtil.wrapServletException(ServletUtil.java:243) ~[tiles-servlet-2.2.2.jar:2.2.2]
at org.apache.tiles.servlet.context.ServletTilesRequestContext.forward(ServletTilesRequestContext.java:243) ~[tiles-servlet-2.2.2.jar:2.2.2]
at org.apache.tiles.servlet.context.ServletTilesRequestContext.dispatch(ServletTilesRequestContext.java:222) ~[tiles-servlet-2.2.2.jar:2.2.2]
at org.apache.tiles.renderer.impl.TemplateAttributeRenderer.write(TemplateAttributeRenderer.java:44) ~[tiles-core-2.2.2.jar:2.2.2]
at org.apache.tiles.renderer.impl.AbstractBaseAttributeRenderer.render(AbstractBaseAttributeRenderer.java:106) ~[tiles-core-2.2.2.jar:2.2.2]
at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:670) ~[tiles-core-2.2.2.jar:2.2.2]
at org.apache.tiles.impl.BasicTilesContainer.render(BasicTilesContainer.java:690) ~[tiles-core-2.2.2.jar:2.2.2]
... 75 common frames omitted
Caused by: org.apache.jasper.JasperException: PWC6033: Error in Javac compilation for JSP

PWC6199: Generated servlet error:
string:///noLayout_jsp.java:7: cannot access java.lang.Object
bad class file: java\lang\Object.class(java\lang:Object.class)
class file has wrong version 52.0, should be 50.0
Please remove or make sure it appears in the correct subdirectory of the classpath*.

noLayout.jsp

  <% response.setHeader("Cache-Control", "no-store, private, must-revalidate, max-stale=0, post-check=0, pre-check=0"); //Forces caches to obtain a new copy of the page from the origin server
response.setHeader("Pragma", "no-cache"); //HTTP 1.0 backward compatibility 
response.setDateHeader("Expires", 0); //Causes the proxy cache to see the page as "stale"
%><%@ page isELIgnored="false"%><!doctype html>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%><%@ taglib uri="http://tiles.apache.org/tags-tiles" prefix="tiles"%>
<html>
 <head>  
  <meta http-equiv="Content-Type" content="text/html;charset=UTF-8">  
<link href="${pageContext.request.contextPath}/css/base.css" rel="stylesheet" type="text/css">

我正在使用 Ivy 进行依赖管理

我从

Tiles 2.2 版、spring 4.0 和码头

Answer 1

一种可能的解决方案是为org.apache.jasper.servlet.JspServlet (tomcat-home/conf/web.xml) 定义compilerSourceVM 和compilerTargetVM (tomcat-home/conf/web.xml)

像这样：

 <servlet>
        <servlet-name>jsp</servlet-name>
        <servlet-class>org.apache.jasper.servlet.JspServlet</servlet-class>
        <init-param>                                   
            <param-name>compilerSourceVM</param-name>
            <param-value>1.8</param-value>
        </init-param>
        <init-param>
            <param-name>compilerTargetVM</param-name>
            <param-value>1.8</param-value>
        </init-param>                                   
    </servlet>

这个配置定义了jasper的编译版本。

更多信息请查看你的tomcat实现的配置属性，例如Tomcat 7 reference doc

你也可以阅读这篇文章，了解如何定义jasper编译器版本Jasper Compiler Version config

Answer 2

string:///noLayout_jsp.java:7: cannot access java.lang.Object
bad class file: java\lang\Object.class(java\lang:Object.class)
class file has wrong version 52.0, should be 50.0

用于处理 JSP 的编译器似乎仍然是 Java 6，但使用了 Java 8 的系统 jar。您是从 Eclipse 启动应用程序，还是将其作为独立应用程序运行时？如果是前者，请确保您还将 JRE 系统库（项目属性 -> Java 构建路径 -> JRE 系统库）设置为 Java 8。仅在 Java 编译器设置中将所有内容设置为 Java 8 是不够的。如果是字母，请检查您的 JSP 配置是否还有指向 Java 6 二进制文件的旧配置。