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base4j分布式缓存（基于j2cache）
There is a newer version: 1.3.1
package com.base4j.cache.utils;

import org.apache.commons.io.IOUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

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

/**
 * Properties文件载入工具类. 可载入多个properties文件, 相同的属性在最后载入的文件中的值将会覆盖之前的值，但以System的Property优先.
 * 
 * @author calvin
 */
public class PropertiesLoader {

	private static final Logger logger = LoggerFactory.getLogger(PropertiesLoader.class);

	private final Properties properties;

	public PropertiesLoader(String... resourcesPaths) {
		properties = loadProperties(resourcesPaths);
	}

	public Properties getProperties() {
		return properties;
	}

	/**
	 * 取出Property。
	 */
	private String getValue(String key) {
		String systemProperty = System.getProperty(key);
		if (systemProperty != null) {
			return systemProperty;
		}
		return properties.getProperty(key);
	}

	/**
	 * 取出String类型的Property,如果都為Null则抛出异常.
	 */
	public String getProperty(String key) {
		String value = getValue(key);
		if (value == null) {
			throw new NoSuchElementException();
		}
		return value;
	}

	/**
	 * 取出String类型的Property.如果都為Null則返回Default值.
	 */
	public String getProperty(String key, String defaultValue) {
		String value = getValue(key);
		return value != null ? value : defaultValue;
	}

	/**
	 * 取出Integer类型的Property.如果都為Null或内容错误则抛出异常.
	 */
	public Integer getInteger(String key) {
		String value = getValue(key);
		if (value == null) {
			throw new NoSuchElementException();
		}
		return Integer.valueOf(value);
	}

	/**
	 * 取出Integer类型的Property.如果都為Null則返回Default值，如果内容错误则抛出异常
	 */
	public Integer getInteger(String key, Integer defaultValue) {
		String value = getValue(key);
		return value != null ? Integer.valueOf(value) : defaultValue;
	}

	/**
	 * 取出Double类型的Property.如果都為Null或内容错误则抛出异常.
	 */
	public Double getDouble(String key) {
		String value = getValue(key);
		if (value == null) {
			throw new NoSuchElementException();
		}
		return Double.valueOf(value);
	}

	/**
	 * 取出Double类型的Property.如果都為Null則返回Default值，如果内容错误则抛出异常
	 */
	public Double getDouble(String key, Integer defaultValue) {
		String value = getValue(key);
		return value != null ? Double.valueOf(value) : defaultValue;
	}

	/**
	 * 取出Boolean类型的Property.如果都為Null抛出异常,如果内容不是true/false则返回false.
	 */
	public Boolean getBoolean(String key) {
		String value = getValue(key);
		if (value == null) {
			throw new NoSuchElementException();
		}
		return Boolean.valueOf(value);
	}

	/**
	 * 取出Boolean类型的Propert.如果都為Null則返回Default值,如果内容不为true/false则返回false.
	 */
	public Boolean getBoolean(String key, boolean defaultValue) {
		String value = getValue(key);
		return value != null ? Boolean.valueOf(value) : defaultValue;
	}

	/**
	 * 载入多个文件, 文件路径使用Spring Resource格式.
	 */
	private Properties loadProperties(String... resourcesPaths) {
		Properties props = new Properties();

		for (String location : resourcesPaths) {

            logger.debug("Loading properties file from path:{}", location);

			InputStream is = null;
			try {
                is = getResourceAsInputStream(location);
				props.load(is);
			} catch (IOException ex) {
                logger.warn("Could not load properties from path:{}, {} ", location, ex.getMessage());
			} finally {
				IOUtils.closeQuietly(is);
			}
		}
		return props;
	}

    public InputStream getResourceAsInputStream(String filePath) {
        assert filePath != null : "filePath must not be null!";
        if (filePath.startsWith("/")) {
            return getDefaultClassLoader().getResourceAsStream(filePath.substring(1));
        } else if (filePath.startsWith("classpath:")) {
            return getResourceAsInputStream(filePath.substring("classpath:".length()));
        } else if (filePath.startsWith("classpath*:")) {
            return getResourceAsInputStream(filePath.substring("classpath*:".length()));
        }
        return getDefaultClassLoader().getResourceAsStream(filePath);
    }

    /**
     * 获得ClassLoader对象
     * @return {@link ClassLoader}
     */
    public static ClassLoader getDefaultClassLoader() {
        ClassLoader cl = null;

        try {
            cl = Thread.currentThread().getContextClassLoader();
        } catch (Exception ignored) {
            ;
        }

        if(cl == null) {
            cl = PropertiesLoader.class.getClassLoader();
            if(cl == null) {
                try {
                    cl = ClassLoader.getSystemClassLoader();
                } catch (Exception ignored) {
                    ;
                }
            }
        }

        return cl;
    }

}