Properties这个读取属性的类我站有教吗？

Question

package cn.jikexueyuan.kafka.ubas.util;import java.util.Enumeration;import java.util.HashMap;import java.util.Map;import java.util.Properties;import org.slf4j.Logger;import org.slf4j.LoggerFactory;/** * @Date May 25, 2015 *  * @Author dengjie *  * @Note This is the single entry point for accessing configuration properties. *  */public class SystemConfig { private static Properties mConfig; private static Logger log = LoggerFactory.getLogger(SystemConfig.class); static { mConfig = new Properties(); try { try { mConfig.load(SystemConfig.class.getClassLoader().getResourceAsStream("system-config.properties")); mConfig.load(SystemConfig.class.getClassLoader().getResourceAsStream("jdbc.properties")); } catch (Exception exp1) { exp1.printStackTrace(); } log.info("Successfully loaded default properties."); if (log.isDebugEnabled()) { log.debug("SystemConfig looks like this ..."); String key = null; Enumeration<Object> keys = mConfig.keys(); while (keys.hasMoreElements()) { key = (String) keys.nextElement(); log.debug(key + "=" + mConfig.getProperty(key)); } } } catch (Exception e) { e.printStackTrace(); } } private SystemConfig() { } /** * Retrieve a property value */ public static String getProperty(String key) { return mConfig.getProperty(key); } public static String getProperty(String key, String defaultValue) { log.debug("Fetching property [" + key + "=" + mConfig.getProperty(key) + "]"); String value = SystemConfig.getProperty(key); if (value == null) { return defaultValue; } return value; } /** * Retrieve a property as a boolean ... defaults to false if not present. */ public static boolean getBooleanProperty(String name) { return getBooleanProperty(name, false); } /** * Retrieve a property as a boolean with specified default if not present. */ public static boolean getBooleanProperty(String name, boolean defaultValue) { String value = SystemConfig.getProperty(name); if (value == null) { return defaultValue; } return (new Boolean(value)).booleanValue(); } /** * Retrieve a property as a int,defaults to 0 if not present. */ public static int getIntProperty(String name) { return getIntProperty(name, 0); } /** * Retrieve a property as a int */ public static int getIntProperty(String name, int defaultValue) { String value = SystemConfig.getProperty(name); if (value == null) { return defaultValue; } try { return Integer.parseInt(value); } catch (NumberFormatException e) { return defaultValue; } } /** *  */ public static int[] getIntPropertyArray(String name, int[] defaultValue, String splitStr) { String value = SystemConfig.getProperty(name); if (value == null) { return defaultValue; } try { String[] propertyArray = value.split(splitStr); int[] result = new int[propertyArray.length]; for (int i = 0; i < propertyArray.length; i++) { result[i] = Integer.parseInt(propertyArray[i]); } return result; } catch (NumberFormatException e) { return defaultValue; } } /** */ public static boolean[] getBooleanPropertyArray(String name, boolean[] defaultValue, String splitStr) { String value = SystemConfig.getProperty(name); if (value == null) { return defaultValue; } try { String[] propertyArray = value.split(splitStr); boolean[] result = new boolean[propertyArray.length]; for (int i = 0; i < propertyArray.length; i++) { result[i] = (new Boolean(propertyArray[i])).booleanValue(); } return result; } catch (NumberFormatException e) { return defaultValue; } } /** */ public static String[] getPropertyArray(String name, String[] defaultValue, String splitStr) { String value = SystemConfig.getProperty(name); if (value == null) { return defaultValue; } try { String[] propertyArray = value.split(splitStr); return propertyArray; } catch (NumberFormatException e) { return defaultValue; } } /** */ public static String[] getPropertyArray(String name, String splitStr) { String value = SystemConfig.getProperty(name); if (value == null) { return null; } try { String[] propertyArray = value.split(splitStr); return propertyArray; } catch (NumberFormatException e) { return null; } } /** * Retrieve all property keys */ public static Enumeration<Object> keys() { return mConfig.keys(); } public static Map<String, String> getPropertyMap(String name) { String[] maps = getPropertyArray(name, ","); Map<String, String> map = new HashMap<String, String>(); try { for (String str : maps) { String[] array = str.split(":"); if (array.length > 1) { map.put(array[0], array[1]); } } } catch (Exception e) { log.error("Get PropertyMap info has error,key is :" + name); e.printStackTrace(); } return map; }}类似这样的类，不知道自己写的话应该要写哪几个方法，想系统地学一下，不知道哪里有教。。谢谢，拜托拜托~