PropertiesDataSourceInfoLookup.java

package jef.database.datasource;

import java.io.IOException;
import java.net.URL;
import java.util.Collection;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;

import jef.common.log.LogUtil;
import jef.common.wrapper.PropertiesMap;
import jef.tools.IOUtils;
import jef.tools.StringUtils;

/**
 * DatasourceLookup implementaion of properties
 * 会在classpath下的指定资源文件，以及System.properties中查找数据源配置
 * @author jiyi
 *
 */
public class PropertiesDataSourceInfoLookup implements DataSourceInfoLookup{
	private String keyOfPrefix="";
	private String keyOfUrl=".url";
	private String keyOfUser=".user";
	private String keyOfPassword=".password";
	private String keyOfDriver=".driver";
	private String location;
	private boolean needLogonInfo=true;
	private PasswordDecryptor passwordDecryptor=PasswordDecryptor.DUMMY;
	private String defaultKey;
	
	private Map<String,DataSourceInfo> cache;
	
	public DataSourceInfo getDataSourceInfo(String dataSourceName) {
		checkInit();
		DataSourceInfo dsi=cache.get(dataSourceName.toUpperCase());
		return dsi;
	}

	private void checkInit() {
		if(cache==null){
			init(new PropertiesMap(System.getProperties()));
			if(StringUtils.isNotEmpty(location!=null)){
				try {
					Enumeration<URL> resources=this.getClass().getClassLoader().getResources(location);
					if(!resources.hasMoreElements()){
						LogUtil.error("No properties file [{}] found.",location);
					}
					for(;resources.hasMoreElements();){
						Map<String,String> properties=IOUtils.loadProperties(resources.nextElement());
						init(properties);						
					}
				} catch (IOException e) {
					LogUtil.exception(e);
				}
			}
		}
	}

	private synchronized void init(Map<String,String> props) {
		Map<String,DataSourceInfo> map;
		if(cache==null){
			map=new HashMap<String,DataSourceInfo>();
			cache=map;
		}else{
			map=cache;
		}
		for(Entry<String,String> e: props.entrySet()){
			if(e.getKey().endsWith(keyOfUrl) && e.getKey().startsWith(keyOfPrefix)){
				int len=e.getKey().length();
				String dsName=e.getKey().substring(keyOfPrefix.length(),len-keyOfPrefix.length()-keyOfUrl.length());
				DataSourceInfo ds=tryGet(props, dsName);
				if(ds!=null){
					map.put(dsName.toUpperCase(), ds);
				}
			}
		}
	}

	private DataSourceInfo tryGet(Map<String,String> p,String dataSourceName) {
		String url=p.get(keyOfPrefix+dataSourceName+keyOfUrl);
		if(url!=null && url.length()>0){
			DataSourceInfoImpl dsi=new DataSourceInfoImpl(url);
			dsi.setUser(p.get(keyOfPrefix+dataSourceName+keyOfUser));
			String password=p.get(keyOfPrefix+dataSourceName+keyOfPassword);
			if(StringUtils.isNotEmpty(password)){
				password=passwordDecryptor.decrypt(password);
			}
			dsi.setPassword(password);
			dsi.setDriverClass(p.get(keyOfPrefix+dataSourceName+keyOfDriver));
			if(needLogonInfo && StringUtils.isEmpty(dsi.getUser())){
				dsi=null;
			}
			return dsi;
		}
		return null;
	}

	/**
	 * 数据源配置在Properties文件中的前缀，举例<pre>
	 * jdbc.ds1.url=jdbc:mysql://localhost:3306/test
	 * jdbc.ds1.user=root
	 * jdbc.ds1.password=123456
	 * </pre>
	 * 在上例中KeyOfPrefix就是 'jdbc.'
	 * @param keyOfPrefix default value is empty
	 */
	public void setKeyOfPrefix(String keyOfPrefix) {
		this.keyOfPrefix = keyOfPrefix;
	}

	/**
	 * 数据源配置在Properties文件中的URL的名称，举例<pre>
	 * jdbc.ds1.url=jdbc:mysql://localhost:3306/test
	 * jdbc.ds1.user=root
	 * jdbc.ds1.password=123456
	 * </pre>
	 * 在上例中KeyOfUrl就是 '.url'
	 * @param keyOfPrefix default valuie is '.url'
	 */
	public void setKeyOfUrl(String keyOfUrl) {
		this.keyOfUrl = keyOfUrl;
	}
	/**
	 * 数据源配置在Properties文件中的username的名称，举例<pre>
	 * jdbc.ds1.url=jdbc:mysql://localhost:3306/test
	 * jdbc.ds1.user=root
	 * jdbc.ds1.password=123456
	 * </pre>
	 * 在上例中KeyOfUser就是 '.user'
	 * @param keyOfUser default valuie is '.user'
	 */
	public void setKeyOfUser(String keyOfUser) {
		this.keyOfUser = keyOfUser;
	}
	/**
	 * 数据源配置在Properties文件中的username的名称，举例<pre>
	 * jdbc.ds1.url=jdbc:mysql://localhost:3306/test
	 * jdbc.ds1.user=root
	 * jdbc.ds1.password=123456
	 * </pre>
	 * 在上例中KeyOfPassword就是 '.password'
	 * @param keyOfPassword default valuie is '.password'
	 */
	public void setKeyOfPassword(String keyOfPassword) {
		this.keyOfPassword = keyOfPassword;
	}
	/**
	 * 数据源配置在Properties文件中的driverClass，举例<pre>
	 * jdbc.ds1.url=jdbc:mysql://localhost:3306/test
	 * jdbc.ds1.user=root
	 * jdbc.ds1.password=123456
	 * jdbc.ds1.driver=org.gjt.mm.mysql.Driver
	 * </pre>
	 * 在上例中KeyOfDriver就是 '.driver'
	 * @param keyOfDriver default valuie is '.driver'
	 */
	public void setKeyOfDriver(String keyOfDriver) {
		this.keyOfDriver = keyOfDriver;
	}
	
	/**
	 * 设置properties文件路径。不设置的话只会使用System.getProperty();
	 * 路径不能以/开头，jef会查找所有classpath下的该名称的资源文件来查找数据库配置
	 * @param localtion
	 */
	public void setLocation(String localtion) {
		this.location = localtion;
	}

	/**
	 * 如果没有配置user或者password的数据源就忽略
	 * @param needLogonInfo
	 */
	public void setNeedLogonInfo(boolean needLogonInfo) {
		this.needLogonInfo = needLogonInfo;
	}

	public void setPasswordDecryptor(PasswordDecryptor passwordDecryptor) {
		this.passwordDecryptor=passwordDecryptor;
	}

	public String getDefaultKey() {
		return defaultKey;
	}

	public void setDefaultKey(String defaultKey) {
		this.defaultKey = defaultKey;
	}
	
	public Collection<String> getAvailableKeys() {
		checkInit();
		return cache.keySet();
	}
}