public String lookup()

in log4j-web/src/main/java/org/apache/logging/log4j/web/WebLookup.java [34:114]
67 lines of code
20 McCabe index (conditional complexity)

    public String lookup(final LogEvent event, final String key) {
        final ServletContext ctx = WebLoggerContextUtils.getServletContext();
        if (ctx == null) {
            return null;
        }

        if (key.startsWith(ATTR_PREFIX)) {
            final String attrName = key.substring(ATTR_PREFIX.length());
            final Object attrValue = ctx.getAttribute(attrName);
            return attrValue == null ? null : attrValue.toString();
        }

        if (key.startsWith(INIT_PARAM_PREFIX)) {
            final String paramName = key.substring(INIT_PARAM_PREFIX.length());
            return ctx.getInitParameter(paramName);
        }

        if ("rootDir".equals(key)) {
            final String root = ctx.getRealPath("/");
            if (root == null) {
                final String msg = "Failed to resolve web:rootDir -- " +
                        "servlet container unable to translate virtual path " +
                        " to real path (probably not deployed as exploded";
                throw new IllegalStateException(msg);
            }
            return root;
        }

        if ("contextPathName".equals(key)) {
            final String path = ctx.getContextPath();
            if (path.trim().contains("/")) {
                final String[] fields = path.split("/");
                for (String field : fields) {
                    if (field.length() > 0) {
                        return field;
                    }
                }
                return null;
            }
            return ctx.getContextPath();
        }

        if ("contextPath".equals(key)) {
            return ctx.getContextPath();
        }

        if ("servletContextName".equals(key)) {
            return ctx.getServletContextName();
        }

        if ("serverInfo".equals(key)) {
            return ctx.getServerInfo();
        }

        if ("effectiveMajorVersion".equals(key)) {
            return String.valueOf(ctx.getEffectiveMajorVersion());
        }

        if ("effectiveMinorVersion".equals(key)) {
            return String.valueOf(ctx.getEffectiveMinorVersion());
        }

        if ("majorVersion".equals(key)) {
            return String.valueOf(ctx.getMajorVersion());
        }

        if ("minorVersion".equals(key)) {
            return String.valueOf(ctx.getMinorVersion());
        }

        if (ctx.getAttribute(key) != null) {
            return ctx.getAttribute(key).toString();
        }

        if (ctx.getInitParameter(key) != null) {
            return ctx.getInitParameter(key);
        }

        ctx.log(getClass().getName() + " unable to resolve key " + Strings.quote(key));
        return null;
    }