Properties文件载入工具类

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. */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;}/** * 取出Property，但以System的Property优先,取不到返回空字符串. */private String getValue(String key) {String systemProperty = System.getProperty(key);if (systemProperty != null) {return systemProperty;}if (properties.containsKey(key)) {        return properties.getProperty(key);    }    return "";}/** * 取出String类型的Property，但以System的Property优先,如果都为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，但以System的Property优先.如果都为Null则返回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，但以System的Property优先.如果都为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，但以System的Property优先.如果都为Null则返回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，但以System的Property优先.如果都为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，但以System的Property优先.如果都为Null则返回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，但以System的Property优先.如果都为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Property，但以System的Property优先.如果都为Null则返回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:" + 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;}}