2.7.0版本getContextPath方法：
```
protected String getContextPath(URL url) {
        String contextPath = url.getPath();
        return contextPath.endsWith("/") ? contextPath.substring(0,contextPath.length()-1) : contextPath;
    }
```
无法将方法置入web容器中，退回2.6.5版本的方法：
```
protected String getContextPath(URL url) {
        int pos = url.getPath().lastIndexOf("/");
        return pos > 0 ? url.getPath().substring(0, pos) : "";
    }
```
使用正常，两个方法应该不等价的。
} catch (UnsupportedEncodingException e) {
            throw new RuntimeException(e.getMessage(), e);
        }
    }
    public static String decode(String value) {
        if (StringUtils.isEmpty(value)) {
            return "";
        }
        try {
            return URLDecoder.decode(value, "UTF-8");
        } catch (UnsupportedEncodingException e) {
            throw new RuntimeException(e.getMessage(), e);
        }
    }
    public String getProtocol() {
        return protocol;
    }
    public URL setProtocol(String protocol) {
        return new URL(protocol, username, password, host, port, path, getParameters());
    }
    public String getUsername() {
        return username;
    }
    public URL setUsername(String username) {
        return new URL(protocol, username, password, host, port, path, getParameters());
    }
    public String getPassword() {
        return password;
    }
    public URL setPassword(String password) {