$.PropertiesLoader.java Source code

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Here is the source code for $.PropertiesLoader.java

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/**
 * Copyright (c) 2005-2011 springside.org.cn
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * 
 * $Id: PropertiesLoader.java 1690 2012-02-22 13:42:00Z calvinxiu $
 */
package ${package}.common.utils.others;

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

    import org.apache.commons.io.IOUtils;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.core.io.DefaultResourceLoader;
    import org.springframework.core.io.Resource;
    import org.springframework.core.io.ResourceLoader;

    /**
     * Properties. ?properties, ???SystemProperty.
     * 
     * @author calvin
     */
    public class PropertiesLoader {

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

        private static ResourceLoader resourceLoader = new DefaultResourceLoader();

        private final Properties properties;

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

        public Properties getProperties() {
            return properties;
        }

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

        /**
         * ?StringProperty,Null.
         */
        public String getProperty(String key) {
            String value = getValue(key);
            if (value == null) {
                throw new NoSuchElementException();
            }
            return value;
        }

        /**
         * ?StringProperty.NullDefault.
         */
        public String getProperty(String key, String defaultValue) {
            String value = getValue(key);
            return value != null ? value : defaultValue;
        }

        /**
         * ?IntegerProperty.Null.
         */
        public Integer getInteger(String key) {
            String value = getValue(key);
            if (value == null) {
                throw new NoSuchElementException();
            }
            return Integer.valueOf(value);
        }

        /**
         * ?IntegerProperty.NullDefault
         */
        public Integer getInteger(String key, Integer defaultValue) {
            String value = getValue(key);
            return value != null ? Integer.valueOf(value) : defaultValue;
        }

        /**
         * ?DoubleProperty.Null.
         */
        public Double getDouble(String key) {
            String value = getValue(key);
            if (value == null) {
                throw new NoSuchElementException();
            }
            return Double.valueOf(value);
        }

        /**
         * ?DoubleProperty.NullDefault
         */
        public Double getDouble(String key, Integer defaultValue) {
            String value = getValue(key);
            return value != null ? Double.valueOf(value) : defaultValue;
        }

        /**
         * ?BooleanProperty.Null,?true/falsefalse.
         */
        public Boolean getBoolean(String key) {
            String value = getValue(key);
            if (value == null) {
                throw new NoSuchElementException();
            }
            return Boolean.valueOf(value);
        }

        /**
         * ?BooleanPropert.NullDefault,?true/falsefalse.
         */
        public Boolean getBoolean(String key, boolean defaultValue) {
            String value = getValue(key);
            return value != null ? Boolean.valueOf(value) : defaultValue;
        }

        /**
         * , Spring Resource?.
         */
        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 {
                    Resource resource = resourceLoader.getResource(location);
                    is = resource.getInputStream();
                    props.load(is);
                } catch (IOException ex) {
                    logger.info("Could not load properties from path:{}, {} ", location, ex.getMessage());
                } finally {
                    IOUtils.closeQuietly(is);
                }
            }
            return props;
        }
    }