求助安装sslexplorer失败

Question

ant install以后输入http://IP:28080提示错误

HTTP ERROR: 500

Unable to compile class for JSP

An error occurred at line: 10 in the jsp file: /WEB-INF/jsp/layouts/layout.jsp
Generated servlet error:
/root/sslexplorer-1.0.0_RC17/sslexplorer/tmp/org/apache/jsp/WEB_002dINF/jsp/layouts/layout_jsp.java:102: cannot access com.sslexplorer.navigation.tags.MenuTag
bad class file: /root/sslexplorer-1.0.0_RC17/sslexplorer/webapp/WEB-INF/classes/com/sslexplorer/navigation/tags/MenuTag.class
class file has wrong version 50.0, should be 49.0
Please remove or make sure it appears in the correct subdirectory of the classpath.
      com.sslexplorer.navigation.tags.MenuTag _jspx_th_navigation_menu_0 = (com.sslexplorer.navigation.tags.MenuTag) _jspx_tagPool_navigation_menu_name_nobody.get(com.sslexplorer.navigation.tags.MenuTag.class);
                                     ^
1 error

RequestURI=/selectCertificateSource.do

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