ActionDispatcherFilter.java 文件源码

@Override
public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws IOException, ServletException {
    HttpServletRequest request = (HttpServletRequest) req;
    HttpServletResponse response = (HttpServletResponse) resp;

    request.setCharacterEncoding(encoding);
    response.setCharacterEncoding(encoding);

    String target = request.getRequestURI();
    if (contextPathLength != 0) {
        target = target.substring(contextPathLength);
    }

    boolean handle = actionHandler.handle(target, request, response);

    if (!handle) {// 没有处理则放行
        chain.doFilter(request, response);
    }
}