SpringMVC乱码问题+异常处理

乱码问题

1. 使用springmvc中自带的过滤器，但是不能解决get乱码

<filter>
   <filter-name>encoding</filter-name>
   <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
   <init-param>
       <param-name>encoding</param-name>
       <param-value>utf-8</param-value>
   </init-param>
</filter>
<filter-mapping>
   <filter-name>encoding</filter-name>
    <!--/*中的*是重点-->
   <url-pattern>/*</url-pattern>
</filter-mapping>

2. 自定义过滤器

@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
			throws IOException, ServletException {
		HttpServletRequest req = (HttpServletRequest) request;
		HttpServletResponse res = (HttpServletResponse) response;
		String method = req.getMethod().toUpperCase();
		if ("POST".equals(method)) {
			req.setCharacterEncoding("utf-8");
			chain.doFilter(req, res);
		} else if ("GET".equals(method)) {
			chain.doFilter(new HttpServletRequestWrapper(req) {
				@Override
				public String getParameter(String name) {
					String newValue = null;
					String oldValue = super.getParameter(name);
					if (oldValue != null) {
						try {
							newValue = new String(oldValue.getBytes("ISO8859-1"), "UTF-8");
						} catch (UnsupportedEncodingException e) {
							e.printStackTrace();
						}
					}
					return newValue;
				}
				@Override
				public String[] getParameterValues(String name) {
					String[] oldValues = super.getParameterValues(name);
					String[] newValues = new String[oldValues.length];
					if (!ArrayUtils.isEmpty(oldValues)) {
						for (int i = 0; i < oldValues.length; i++) {
							try {
								newValues[i] = 
new String(oldValues[i].getBytes("ISO8859-1"), 				"UTF-8");
							} catch (UnsupportedEncodingException e) {
								e.printStackTrace();
							}
						}
					}
					return newValues;
				}
			}, res);
		}
	}

异常处理

1. 自定义异常处理类
   实现接口：HandlerExceptionResolver
   实现resolverException方法

@Component
public class MyExceptionResolver implements HandlerExceptionResolver {


    public ModelAndView resolveException(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o, Exception e) {
        System.out.println("进入了异常处理类");

        System.out.println(o);
        System.out.println(o.getClass());

        System.out.println("错误信息:"+e.getMessage());

        //页面跳转，跳转到错误页

        ModelAndView mv=new ModelAndView();
        mv.setViewName("error");
        mv.addObject("errMsg", e.getMessage());
        return mv;
    }
}

springmvc-servlet.xml配置

<!--简单异常处理类配置-->
    <bean class="org.springframework.web.servlet.handler.SimpleMappingExceptionResolver">
        <property name="exceptionMappings">
            <props>
                <!--
                    key:匹配的异常类型
                    value：逻辑视图名
                -->
                <prop key="java.lang.Exception">error</prop>
                <!--<prop key="java.lang.NullPointerException">error</prop>-->
            </props>
        </property>
    </bean>

2. 使用springmvc中提供的简单异常处理类
   SimpleMappingExceptionReslover 在xml中将其创建对象
   需要在xml中进行启动配置
   在错误页面可以使用jsp内置对象exception来显示错误信息，exception使用需要在page指令中添加isErrorPage=“true”