网上看的这篇文章介绍的还是比较详细的：

创建公众号菜单

package com.picahealth.wechat.wechat.pojo;

/**
 * 按钮的基类
 * 
 */
public class Button {
          
   
	private String name;

	public String getName() {
          
   
		return name;
	}

	public void setName(String name) {
          
   
		this.name = name;
	}
}

package com.picahealth.wechat.wechat.pojo;


/**
 * 普通按钮（子按钮）
 *
 */
public class CommonButton extends Button {
          
   
	private String type;
	private String key;
	private String url;
	private String appid;
	private String pagepath;

	public String getAppid() {
          
   
		return appid;
	}

	public void setAppid(String appid) {
          
   
		this.appid = appid;
	}

	public String getPagepath() {
          
   
		return pagepath;
	}

	public void setPagepath(String pagepath) {
          
   
		this.pagepath = pagepath;
	}

	public String getType() {
          
   
		return type;
	}

	public void setType(String type) {
          
   
		this.type = type;
	}

	public String getKey() {
          
   
		return key;
	}

	public void setKey(String key) {
          
   
		this.key = key;
	}

	public String getUrl() {
          
   
		return url;
	}

	public void setUrl(String url) {
          
   
		this.url = url;
	}
}

package com.picahealth.wechat.wechat.pojo;


/**
 * 复杂按钮（父按钮）
 *
 */
public class ComplexButton extends Button {
          
   
	private Button[] sub_button;

	public Button[] getSub_button() {
          
   
		return sub_button;
	}

	public void setSub_button(Button[] sub_button) {
          
   
		this.sub_button = sub_button;
	}
}

package com.picahealth.wechat.wechat.pojo;

/**
 * 菜单
 *
 */
public class Menu {
          
   
	private Button[] button;

	public Button[] getButton() {
          
   
		return button;
	}

	public void setButton(Button[] button) {
          
   
		this.button = button;
	}
}

回调接口

<dependency>
    <groupId>dom4j</groupId>
    <artifactId>dom4j</artifactId>
    <version>1.6.1</version>
</dependency>
<dependency>
    <groupId>com.thoughtworks.xstream</groupId>
    <artifactId>xstream</artifactId>
    <version>1.3.1</version>
</dependency>

签名验证工具类，官网有提供：

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