src/com/tm/common/wechat/pay/util/MessageUtil.java

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package com.tm.common.wechat.pay.util;

import java.util.Map;
import java.util.Map.Entry;

public class MessageUtil {
	/**
	 * @param params
	 * @return
	 * map转为xml
	 */
	public static String toXml(Map<String, Object> params) throws Exception{
		StringBuilder xml = new StringBuilder();
		xml.append("<xml>");
		for (Entry<String, Object> entry : params.entrySet()) {
			String key   = entry.getKey();
			String value = entry.getValue()+"";
			// 略过空值
			if (isBlank(value)) continue;
			xml.append("<").append(key).append(">");
				xml.append(entry.getValue());
			xml.append("</").append(key).append(">");
		}
		xml.append("</xml>"); 
		return xml.toString();
	}
	protected static boolean isBlank(String str) {
		return str == null || "".equals(str.trim());
	}
}