web 工程下 java操作属性文件保存在classes下的读写操作

来源：互联网发布：手机编程软件java 编辑：程序博客网时间：2024/05/16 10:30

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Enumeration;
import java.util.Properties;

import org.apache.commons.lang.StringUtils;

public class PropertiesUtil {
   // 根据key读取value
   public static String readValue(String filePath, String key) {
       InputStream in = null;
       String value = null;
       try {
           Properties props = new Properties();
           if (StringUtils.isBlank(filePath))
               filePath = "/constants.properties";
           in = (new PropertiesUtil()).getClass()
                   .getResourceAsStream(filePath);
           props.load(in);
           if(props.containsKey(key)){
               value = props.getProperty(key);
            }
       } catch (Exception e) {

       } finally {
           try {
               if (in != null) {
                   in.close();
                   in = null;
               }
           } catch (Exception e) {

           }
       }
       return value;
   }

   // 读取properties的全部信息
   @SuppressWarnings("unchecked")
   public static void readProperties(String filePath) {
       InputStream in = null;
       try {
           Properties props = new Properties();
           if (StringUtils.isBlank(filePath))
               filePath = "/constants.properties";
           in = (new PropertiesUtil()).getClass()
                   .getResourceAsStream(filePath);
           props.load(in);
           Enumeration en = props.propertyNames();
           while (en.hasMoreElements()) {
               String key = (String) en.nextElement();
               String Property = props.getProperty(key);
               System.out.println(key + Property);
           }
       } catch (Exception e) {
           // e.printStackTrace();
           // System.err.println("ConfigInfoError" + e.toString());
       }
   }

   // 写入properties信息
   public static void writeProperties(String filePath, String parameterName,
           String parameterValue) {
       OutputStream fos = null;
       try {
           Properties prop = new Properties();
           if (StringUtils.isBlank(filePath))
               filePath = "constants.properties";
           fos = new FileOutputStream((new PropertiesUtil()).getClass().getResource("/").getPath()+filePath);
           prop.setProperty(parameterName, parameterValue);
           prop.store(fos, "Update '" + parameterName + "' value");
       } catch (IOException e) {
           // e.printStackTrace();
       }finally {
           try {
               if(fos != null) {
                   fos.close();
                   fos = null;
               }
           } catch (Exception e) {

           }
       }
   }

   public static void main(String args[]) {
       String filePath = "constants.properties";
       PropertiesUtil.writeProperties(filePath, "qq1112", "ww222111nnnmmmm");
       System.out.println(PropertiesUtil.readValue("/"+filePath, "qq1112"));
   }
}