JAVAWEB系统启动时，初始化配置文件信息

第一步写Properties工具类，如下：

import java.util.Properties;

public class PropertiesUtil {

private static Properties jdbc = new Properties();
private static Properties system = new Properties();

private PropertiesUtil() {
}

public static Properties getJdbc() {
return jdbc;
}

public static void setJdbc(Properties jdbc) {
PropertiesUtil.jdbc = jdbc;
}

public static Properties getSystem() {
return system;
}

public static void setSystem(Properties system) {
PropertiesUtil.system = system;
}

public static String getJdbcProperty(String key) {
return jdbc.getProperty(key);
}

public static String getJdbcProperty(String key, String defaultValue) {
String value = jdbc.getProperty(key);
if (value == null || value.trim().isEmpty()) {
return defaultValue;
}
return value;
}

public static String getSystemProperty(String key) {
return system.getProperty(key);
}

public static String getSystemProperty(String key, String defaultValue) {
String value = system.getProperty(key);
if (value == null || value.trim().isEmpty()) {
return defaultValue;
}
return value;
}

}

第二步，写启动监听器如下：

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

import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.jeecms.cms.webservices.util.PropertiesUtil;

/**
* 系统启动时加载配置文件信息
*
* @author 罗勇
*
* @date 2014-4-2
*/
public class InitSystemListener implements ServletContextListener {

private static final Logger LOG = LoggerFactory.getLogger(InitSystemListener.class);

public void contextInitialized(ServletContextEvent servletContextEvent) {
this.initSystem();
}

/**
* 初始化配置文件信息
*/
private void initSystem() {
// 加载配置文件
PropertiesUtil.setJdbc(getProperties("jdbc.properties"));
PropertiesUtil.setSystem(getProperties("system.properties"));
}

private Properties getProperties(String propertiesName) {
Properties props = new Properties();
InputStream is = null;
try {
is = getClass().getResourceAsStream("/../config/" + propertiesName);
props.load(is);
LOG.info("初始化配置文件" + propertiesName);
} catch (IOException e) {
LOG.error("初始化配置文件" + propertiesName + "出现异常", e);
} finally {
try {
if (is != null)
is.close();
} catch (IOException e) {
LOG.error("初始化配置文件,关闭is流出现异常", e);
}
}
return props;
}

public void contextDestroyed(ServletContextEvent servletContextEvent) {

}
}

第三部，在web.xml中添加如下配置：

<listener>

<listener-class>com.jeecms.cms.service.InitSystemListener</listener-class>

</listener>