package com.blog51cto.lavasoft.ds;

import java.util.*;
import java.util.regex.Pattern;
import java.util.regex.Matcher;
import java.io.InputStream;

/**
* Created by IntelliJ IDEA.
* User: leizhimin
* Date: 2008-3-19 23:22:38
* Company: LavaSoft(http://lavasoft.blog.51cto.com)
* 数据源配置工具
*/
public class DataSourceConfig {
    private static Map<String, String> defcfgmap;

    //初始化默认配置参数
    static {
        defcfgmap = new HashMap<String, String>();
        defcfgmap.put("driverClassName", "");
        defcfgmap.put("url", "");
        defcfgmap.put("user", "");
        defcfgmap.put("password", "");
        defcfgmap.put("type", "javax.sql.DataSource");
        defcfgmap.put("initCreate", "12");
        defcfgmap.put("maxIdle", "8");
        defcfgmap.put("maxWait", "10");
        defcfgmap.put("maxActive", "5");
        defcfgmap.put("validationQuery", "");
    }

    /**
     * 获取数据源配置信息,本方法接受两种配置文件类型,xml和properties类型.
     *
     * @param cfgFilePath 配置文件的名
     * @return 配置参数Map
     * @throws Exception
     */
    public static Map<String, String> getConfigParameter(String cfgFilePath) throws Exception {
        Map<String, String> mcfg = new HashMap<String, String>();
        Pattern pp = Pattern.compile(".+properties");
        Pattern px = Pattern.compile(".+xml");
        Matcher mp = pp.matcher(cfgFilePath);
        Matcher mx = px.matcher(cfgFilePath);
        InputStream in = DataSourceConfig.class.getResourceAsStream(cfgFilePath);
        Properties prop = new Properties();
        if (mp.matches()) {
            prop.load(in);
            Enumeration<String> enu = (Enumeration<String>) prop.propertyNames();
            while (enu.hasMoreElements()) {
                String key = enu.nextElement();
                String value = prop.getProperty(key);
                mcfg.put(key, value);
            }
            in.close();
        } else if (mx.matches()) {
            prop.loadFromXML(in);
            Enumeration<String> enu = (Enumeration<String>) prop.propertyNames();
            while (enu.hasMoreElements()) {
                String key = enu.nextElement();
                String value = prop.getProperty(key);
                mcfg.put(key, value);
            }
            in.close();
        } else {
            throw new Exception("数据源配置文件必须为xml或者properties文件,请检查配置!");
        }
        //检查没有配置的属性,并通过默认的属性值进行设置
        Set<Map.Entry<String, String>> def = defcfgmap.entrySet();
        for (Map.Entry<String, String> d : def) {
            if (!mcfg.containsKey(d.getKey())) {
                mcfg.put(d.getKey(), d.getValue());
            }
        }
        return mcfg;
    }

    /**
     * 获取默认的数据源配置信息
     *
     * @return
     */
    private static String getDefaultConfig() {
        return getConfig(defcfgmap);
    }

    /**
     * 返回数据源配置信息的文本表述
     *
     * @param map 配置信息Map
     * @return 数据源配置信息的文本表述
     */

    private static String getConfig(Map<String, String> map) {
        StringBuffer sb = new StringBuffer("数据源配置参数:\n");
        for (Map.Entry<String, String> ent : map.entrySet()) {
            sb.append(ent.getKey()).append("=").append(ent.getValue()).append("\n");
        }
        return sb.toString();
    }

    /**
     * 测试配置参数获取工具
     *
     * @param args
     * @throws Exception
     */
    public static void main(String args[]) throws Exception {
        Map<String, String> mcfg = getConfigParameter("dscfg.xml");
        String cfg = getConfig(mcfg);
        System.out.println(cfg);
    }
}

driverClassName=com.mysql.jdbc.Driver
url=jdbc:mysql://127.0.0.1:3306/mysql
user=root
password=leizhimin

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE properties SYSTEM "http://java.sun.com/dtd/properties.dtd">
<properties>
<comment>JDBC数据库连接池实现</comment>
<entry key="user">root</entry>
<entry key="password">leizhimin</entry>
<entry key="url">jdbc:mysql://127.0.0.1:3306/mysql</entry>
<entry key="driverClassName">com.mysql.jdbc.Driver</entry>
</properties>