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。
* @see #getParameter(String, int)
     * @deprecated Replace to <code>getParameter(String, int)</code>
     */
    @Deprecated
    public int getIntParameter(String key, int defaultValue) {
        return getParameter(key, defaultValue);
    }
    /**
     * @see #getPositiveParameter(String, int)
     * @deprecated Replace to <code>getPositiveParameter(String, int)</code>
     */
    @Deprecated
    public int getPositiveIntParameter(String key, int defaultValue) {
        return getPositiveParameter(key, defaultValue);
    }
    /**
     * @see #getParameter(String, boolean)
     * @deprecated Replace to <code>getParameter(String, boolean)</code>
     */
    @Deprecated
    public boolean getBooleanParameter(String key) {
        return getParameter(key, false);
    }
    /**
     * @see #getParameter(String, boolean)
     * @deprecated Replace to <code>getParameter(String, boolean)</code>
     */
    @Deprecated
    public boolean getBooleanParameter(String key, boolean defaultValue) {
        return getParameter(key, defaultValue);