examcloud-components/src/main/java/cn/com/qmth/examcloud/commons/util/PropertiesUtil.java

package cn.com.qmth.examcloud.commons.util;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.Properties;
import java.util.Set;

import org.apache.commons.io.IOUtils;
import org.apache.commons.lang.StringUtils;

import com.google.common.collect.Sets;

import cn.com.qmth.examcloud.commons.exception.ExamCloudRuntimeException;
import cn.com.qmth.examcloud.commons.logging.ExamCloudLog;
import cn.com.qmth.examcloud.commons.logging.ExamCloudLogFactory;

/**
 * 类注释
 *
 * @author WANGWEI
 * @date 2018年10月8日
 * @Copyright (c) 2018-2020 WANGWEI [QQ:522080330] All Rights Reserved.
 */
public class PropertiesUtil {

	private static final ExamCloudLog LOG = ExamCloudLogFactory.getLog(PropertiesUtil.class);

	private static final Properties PROPS = new Properties();

	private static final Set<String> PROP_FILES = Sets.newConcurrentHashSet();

	static {
		init();
	}

	/**
	 * 构造函数
	 *
	 */
	private PropertiesUtil() {
	}

	/**
	 * 初始化方法
	 *
	 * @author WANGWEI
	 */
	public static void init() {
		configure(PathUtil.getResoucePath("resource.properties"));
	}

	/**
	 * 加载配置文件并观察配置文件
	 *
	 * @author WANGWEI
	 * @param path
	 */
	public static synchronized void configure(String path) {
		if (StringUtils.isBlank(path)) {
			return;
		}
		try {
			File file = new File(path);

			if (PROP_FILES.contains(file.getCanonicalPath())) {
				return;
			}

			loadFromFile(file, PROPS);

			PROP_FILES.add(file.getCanonicalPath());
		} catch (Exception e) {
			LOG.error("Fail to load and watch file [" + path + "].", e);
		}
	}

	/**
	 * @param path
	 * @param props
	 */
	public static void loadFromDir(String path, Properties props) {
		File dir = new File(path + "");
		if ((!dir.exists()) || (!dir.isDirectory())) {
			LOG.error("directory [" + path + "] is illegal.");
			return;
		}

		LOG.info("Loading all Properties files from path [" + path + "].");

		File[] files = dir.listFiles();
		if (null == files || 0 == files.length) {
			return;
		}
		for (File file : files) {
			if (file.isDirectory()) {
				continue;
			}
			if (file.getName().toLowerCase().endsWith(".properties")) {
				loadFromFile(file, props);
			}
		}
	}

	/**
	 * @param resourceName
	 * @param props
	 */
	public static void loadFromResource(String resourceName, Properties props) {
		if (null != PropertiesUtil.class.getClassLoader()) {
			InputStream in = PropertiesUtil.class.getClassLoader()
					.getResourceAsStream(resourceName);

			loadFromStream(in, props);
		} else {
			throw new ExamCloudRuntimeException("fail to get class loader");
		}
	}

	/**
	 * @param file
	 * @param props
	 * @throws IOException
	 */
	public static void loadFromFile(File file, Properties props) {
		if (null == file) {
			LOG.error("file is null.");
			return;
		}
		if (!file.isFile()) {
			LOG.error("file is not a normal file.");
			return;
		}

		String path = PathUtil.getCanonicalPath(file);
		LOG.info("Loading properties from file [" + path + "]");

		try {
			loadFromStream(new FileInputStream(file), props);
		} catch (Exception e) {
			throw new ExamCloudRuntimeException(e);
		}
	}

	/**
	 * @param is
	 * @param props
	 */
	public static void loadFromStream(InputStream is, Properties props) {
		BufferedReader reader = null;
		try {
			reader = new BufferedReader(new InputStreamReader(is, "UTF-8"));
			props.load(reader);
		} catch (IOException e) {
			throw new ExamCloudRuntimeException(e);
		} finally {
			IOUtils.closeQuietly(reader);
			IOUtils.closeQuietly(is);
		}
	}

	/**
	 * @param key
	 * @return
	 */
	public static String getString(String key) {
		String value = PROPS.getProperty(key);
		if (StringUtils.isNotBlank(value)) {
			return value.trim();
		} else {
			if (LOG.isDebugEnabled()) {
				LOG.debug("No  property key named [" + key + "] is configured.");
			}
			return null;
		}
	}

	/**
	 * @param key
	 * @param defaultValue
	 * @return
	 */
	public static String getString(String key, String defaultValue) {
		String value = getString(key);
		if (null != value) {
			return value;
		}
		return defaultValue;
	}

	/**
	 * @param key
	 * @param defaultValue
	 * @return
	 */
	public static int getInt(String key, int defaultValue) {
		String value = getString(key);
		if (null != value) {
			try {
				return Integer.parseInt(value);
			} catch (NumberFormatException e) {
				PROPS.setProperty(key, String.valueOf(defaultValue));
				return defaultValue;
			}
		}
		return defaultValue;
	}

	/**
	 * @param key
	 * @param defaultValue
	 * @return
	 */
	public static long getLong(String key, long defaultValue) {
		String value = getString(key);
		if (null != value) {
			try {
				return Long.parseLong(value);
			} catch (NumberFormatException e) {
				return defaultValue;
			}
		}
		return defaultValue;
	}

	/**
	 * 获取boolean
	 *
	 * @author WANGWEI
	 * @param key
	 * @param defaultVale
	 * @return
	 */
	public static boolean getBoolean(String key, boolean defaultVale) {
		String value = getString(key);
		if (null == value) {
			return defaultVale;
		}
		if (value.equals("true")) {
			return true;
		} else if (value.equals("false")) {
			return false;
		} else {
			return defaultVale;
		}
	}
}