Java J2EE读取配置文件

package com;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import javax.naming.InitialContext;

import java.io.File;

import java.io.FileFilter;

import java.io.FileReader;

import java.util.Iterator;

import java.util.Map;

import java.util.Map.Entry;

import java.util.Properties;

import java.util.concurrent.ConcurrentHashMap;

/**

 * 读取配置文件

 */

public class ReadProperty {

	private static final Logger logger = LoggerFactory.getLogger(Globals.class);

	private static String confHome = null;

	//并发，线程安全的map

	private static Map<String, String> confProperties = new ConcurrentHashMap<>();

	private static Map<String, File> confFiles = new ConcurrentHashMap<>();

	//加载成功

	private static boolean loadingSuccess = true;

    /**

     * 加载配置文件

	 */

	private synchronized static void loadProperties() {

		//如果没有加载成功，返回

		if ( !loadingSuccess ) {

            return;

		}

		//如果加载的文件是空的

		if (confProperties.isEmpty()) {

			//如果电脑环境变量中为空

			if (confHome == null) {

	        	confHome = System.getProperty("CONF_HOME");

	        }

	        //如果web.xml中没配

	        if (confHome == null) {

	            try {

	                InitialContext context = new InitialContext();

	                confHome = (String)context.lookup("java:comp/env/CONF_HOME");

	            } catch(Exception e) {

	            	logger.warn("Can not find jini name {}", "java:comp/env/CONF_HOME");

	            }

	        }

	        //如果还是为空，就找本机路径下的ProtectionDomain/CodeSource/Location/getFile/WEB-INF/文件夹/conf

	        if (confHome == null) {

	        	confHome = (new InitWebPath()).getRootPath() + "WEB-INF" + File.separator + "conf";

	        }

	        //是否是文件夹

		   try {

			   File dirFile = new File(confHome);

			   if(!dirFile.exists() || (!dirFile.isDirectory())){ 

				   logger.warn("Can not find home or is not directory!\n{}", confHome);

				   loadingSuccess = false;

				   return;

			   }

			   //获取所有文件后缀是.properties的文件名

			   File[] files = dirFile.listFiles(new FileFilter() {

				   @Override

				   public boolean accept(File file) {

					   String fileName = file.getName();

					   int pos = fileName.lastIndexOf(".properties");//最后一个匹配的 db.xml和db.xml.xml

					   if (pos != -1) {  

						   confFiles.put(fileName.substring(0, pos), file);//文件名与文件关联 key value 

						   return true;

					   } else {

						   pos = fileName.lastIndexOf(".xml");

						   confFiles.put(fileName.substring(0, pos), file);

						   return false;

					   }

				   }

			   }

			   );

			   //迭代文件，读取key value

			   for(File file : files) {

				   Properties fileProperties = new Properties();

				   fileProperties.load(new FileReader(file));

				   Iterator<Entry<Object, Object>> iterProp = fileProperties.entrySet().iterator();

				   while(iterProp.hasNext()) {

					   Entry<Object, Object> row = iterProp.next();

					   Object key = row.getKey();

					   Object value = row.getValue();

					   if (null!=key && null!=value) {

						   confProperties.put(key.toString(), value.toString());

					   }

				   }

			   }

		   } catch(Exception e) {

			   loadingSuccess = false;

		   }

		}

	}

	/**

	 * 读取配置文件信息

	 * @param name key

	 * @return value

	 */

	public static String getProperty(String name) {

		if (confProperties.isEmpty()) {

			loadProperties();

		}

		return confProperties.get(name);

	}

	static class InitWebPath{

		public String getRootPath() {

			String url = InitWebPath.class.getProtectionDomain().getCodeSource().getLocation().getFile();

			String filePath = "";

			try {

				filePath = java.net.URLDecoder.decode(url, "utf-8");

			} catch (Exception e) {

				logger.error(e.getMessage(), e);

			}

			final String fileFlag = "file:";

			if (filePath.startsWith(fileFlag)) {

				filePath = filePath.substring(fileFlag.length());

			}

			final String applicationFlag = "WEB-INF";

			return filePath.substring(0, filePath.lastIndexOf(applicationFlag));

		}

	}

}