1.首先上目錄結構：

2.部署到tomcat，在servlet中測試，測試程式碼：

package test;

import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;
import java.util.ResourceBundle;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import utils.ReadFile;
import utils.readFile.SysConfig;

/**
 * Servlet implementation class testEvery
 */
@WebServlet("/testEvery")
public class testEveryServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public testEveryServlet() {
        super();
        // TODO Auto-generated constructor stub
    }
    /**
     * 訪問url：http://localhost:8080/demoProj/testEveryServlet
     */
	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		response.getWriter().append("Served at: ").append(request.getContextPath());
		String path = request.getSession().getServletContext().getRealPath("/config/sysconfig.properties");
		System.out.println("doGet讀取到的/WEB-INF/config/sysconfig.properties:path:"+path);
		String url = request.getSession().getServletContext().getRealPath("/WEB-INF/config/config.properties");
		System.out.println("doGet讀取到的/WEB-INF/config/config.properties:url:"+url);
		/**
		 * 結果：
		 * doGet:path:D:\tomcat7\wtpwebapps\demoProj\config\sysconfig.properties
		 * doGet:url:D:\tomcat7\wtpwebapps\demoProj\WEB-INF\config\config.properties
		 */
		//只能獲取src下面的
		 InputStream in = this.getServletContext().getResourceAsStream("/WEB-INF/classes/config/test.properties");  
	        Properties prop = new Properties();  //map  
	        prop.load(in);  
	        String url1 = prop.getProperty("url"); 
	        System.out.println("獲取到的url1:"+url1);//獲取到的url1:www.baidu.com
	        
	        //不可獲取
	        InputStream in2 = this.getServletContext().getResourceAsStream("/WEB-INF/config.properties");  
	        Properties prop2 = new Properties();  //map  
	        prop.load(in2);  
	        String url2 = prop2.getProperty("url"); 
	        System.out.println("獲取到的url2:"+url2);//獲取到的url2:null
	        
	      //不可獲取
	        InputStream in3 = this.getServletContext().getResourceAsStream("/webcontent.properties");  
	        Properties prop3 = new Properties();  //map  
	        prop.load(in3);  
	        String url3 = prop3.getProperty("url"); 
	        System.out.println("獲取到的url3:"+url3);//獲取到的url3:null
	        
	      //不可獲取
	        InputStream in4 = this.getServletContext().getResourceAsStream("/config/wcc.properties");  
	        Properties prop4 = new Properties();  //map  
	        prop.load(in4);  
	        String url4 = prop4.getProperty("url"); 
	        System.out.println("獲取到的url4:"+url4);//獲取到的url4:null
		
		// 讀取src下config包中的testJava.java
//		InputStream in = ReadFile.class.getResourceAsStream("/config/testJava.java");//in為null
//		byte[] a=new byte[100];
//		in.read(a, 0, 900);
//		System.out.println("讀取src下config包中的testJava.java的輸入流in的內容toString："+in.toString());
//		System.out.println("讀取到的a:"+a);
		String fileName3 = ReadFile.class.getResource("/config/test.properties").getFile();
		System.out.println("讀取src下config包中的test.properties:"+fileName3);
//輸出：讀取src下config包中的test.properties:/D:/tomcat7/wtpwebapps/demoProj/WEB-INF/classes/config/test.properties
//		in.close();
		
		// 讀取src下 基名為myproperties的properties檔案，獲取其中name配置值
		String value = ResourceBundle.getBundle("myproperties").getString("name");
		System.out.println("獲取到的myproperties.properties的值value："+value);
//輸出：獲取到的myproperties.properties的值value：myname
		
		// 讀取src下myproperties.properties
		InputStream in1 = ReadFile.class.getResourceAsStream("/myproperties.properties");
		Properties properties = new Properties();
		properties.load(in1);
		String value2 = properties.getProperty("name"); // 獲得name屬性
		System.out.println("獲取到的myproperties.properties的值value2："+value2);
//獲取到的myproperties.properties的值value2：myname		
		
		//讀取src下的
		String sensitiveWordsServerPath1 = SysConfig.getSysParam("sensitiveWords_server_path1");
		System.out.println("獲取的sensitiveWordsServerPath1:"+sensitiveWordsServerPath1);
		//獲取的sensitiveWordsServerPath1:/datacms/htdocs/html/cctv/sensitiveWords/sws.xlsx
		
		//讀取src下的
		String pp = prop("sensitiveWords_server_path1");
		System.out.println("pp:"+pp);//pp:/datacms/htdocs/html/cctv/sensitiveWords/sws.xlsx
	}
	
	public String prop(String url){
		InputStream inputStream = this.getClass().getClassLoader().getResourceAsStream("config/sysconfig.properties");
		Properties p  =   new  Properties();  
		try {
			p.load(inputStream);
		} catch (Exception e) {
			e.printStackTrace();
		}
		System.out.println("p:"+p);
		return p.getProperty(url);
	}
	
	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(request, response);
		String path = request.getSession().getServletContext().getRealPath("/config/sysconfig.properties");
		System.out.println("doPost:path:"+path);
	}

}
 

網上大量的讀取配置檔案的都是從src目錄下，只有以下是從WebContent目錄下讀取的：

String path = request.getSession().getServletContext().getRealPath("/config/sysconfig.properties");
		System.out.println("doGet讀取到的/WEB-INF/config/sysconfig.properties:path:"+path);
		String url = request.getSession().getServletContext().getRealPath("/WEB-INF/config/config.properties");
		System.out.println("doGet讀取到的/WEB-INF/config/config.properties:url:"+url);
		/**
		 * 結果：
		 * doGet:path:D:\tomcat7\wtpwebapps\demoProj\config\sysconfig.properties
		 * doGet:url:D:\tomcat7\wtpwebapps\demoProj\WEB-INF\config\config.properties
		 */
 

另：目前還沒發現可以不啟動tomcat，直接從當前專案WebContent目錄下讀取配置檔案的簡便方法。（不是從硬碟目錄下，有些方法很複雜），有解決方法的同學請貢獻出來。

附上SysConfig.java

package utils.readFile;

import java.io.FileOutputStream;
import java.io.OutputStream;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;
import java.util.Properties;

import org.apache.log4j.Logger;

import com.alibaba.fastjson.JSONArray;
import com.alibaba.fastjson.JSONObject;

public class SysConfig {
	
	private static Logger logger = Logger.getLogger(SysConfig.class);
	
	/**
	 * 將本類定義為singleton類
	 */
	private SysConfig(){		
	}
	private static SysConfig mConfig= new SysConfig();
	private Map<String,String> params = null;
	private static String CONFIG_FILE="/config/sysconfig.properties";
	private static String CONFIG_FILE_PATH = SysConfig.class.getClassLoader().getResource("").getPath().substring(1) + CONFIG_FILE;
	
	public static String getSysParam(String param) {
		return getAllParams().get(param);	   	
	}
	
	public static Map<String,String> getAllParams() {
		synchronized(mConfig){
			if(mConfig.params==null){				
				mConfig.readConfig();
			}			
		}
		System.out.println("mConfig.params:"+mConfig.params);
		return mConfig.params;
	}
	
	/**
	 * 過載配置檔案
	 */
	public static void reloadConfig(JSONArray array) {
		try{
			Properties props = new Properties();
			for(int i=0;i<array.size();i++){
				JSONObject o = array.getJSONObject(i);
				String key = o.keySet().iterator().next();
				String value = o.getString(key);
				mConfig.params.put(key, value);
				props.setProperty(key, value);
			}
			String configFilePath = CONFIG_FILE_PATH;
			if(!isLocal()){
				configFilePath = "/" + CONFIG_FILE_PATH;
			}
			OutputStream out = new FileOutputStream(configFilePath); 
			props.store(out, "update");
		}catch(Exception e){
			logger.info("may error config");
		}
		
	}
	
	private void readConfig() {
			try {			
				Properties props = new Properties();
				props.load(SysConfig.class.getResourceAsStream(CONFIG_FILE));
				this.propertisToCache(props);
	 		} catch (Exception e) {
	 			logger.info("may error config");
			}
	}
	
	/**
	 * 將配置寫入記憶體
	 * @param properties
	 */
	private void propertisToCache(Properties props){
		mConfig.params = new HashMap<String,String>();
		Enumeration  e = props.propertyNames();
		while(e.hasMoreElements()) {
			String key = (String)e.nextElement();
			String value = props.getProperty(key);
			params.put(key, value);
		}	
		if(isLocal()) {
			params.put("root_path", params.get("root_path_local"));
			params.put("root_path_issue_temp", params.get("root_path_issue_temp_local"));
			params.put("root_path_issue", params.get("root_path_issue_local"));
		} else {
			params.put("root_path", params.get("root_path_server"));
			params.put("root_path_issue_temp", params.get("root_path_issue_temp_server"));
			params.put("root_path_issue", params.get("root_path_issue_server"));
		}
	}
	
	/**
	 * 判斷系統型別
	 * @return：true為windows系統
	 */
	public static boolean isLocal() {
		if (System.getProperty("os.name").contains("Windows")) {
			return true;
		}
		logger.info("os is : " + System.getProperty("os.name"));
		return false;
	}
	
}