1. 基于 JDK 8 time包的时间工具类

#bysocket

Author: JeffLi1993

src/org/javacore/collection/util/CollectionsT.java

@@ -28,21 +28,33 @@ public class CollectionsT{
 	public static void main(String[] args){
 		// 测试集合工具类Sort方法
 		testSort();
+		testAddAll();
 	}
 
 	/**
 	 * 测试集合工具类Sort方法
 	 */
-	private static void testSort(){
-		List<Integer> teams = new ArrayList<Integer>();
-		teams.add(1);
-		teams.add(3);
-		teams.add(2);
-		teams.add(4);
-		// 调用集合工具类Sort方法
-		Collections.sort(teams);
-		
-		System.out.println("Teams:");
-		System.out.print("\t" + teams + "\n");
-	}
+private static void testSort(){
+	List<Integer> list = new ArrayList<Integer>();
+	list.add(1);
+	list.add(3);
+	list.add(2);
+	list.add(4);
+	// 调用集合工具类Sort方法
+	Collections.sort(list);
+
+	System.out.println("list sorted:");
+	System.out.print("\t" + list + "\n");
+}
+
+private static void testAddAll() {
+	List<String> list = new ArrayList<>();
+	list.add("s2");
+	list.add("s4");
+	list.add("s1");
+	list.add("s3");
+	System.out.println(list);
+	Collections.addAll(list, "s5","s7",null,"s9");
+	System.out.println(list);
+}
 }

src/org/javacore/time/TimeUtil.java

@@ -0,0 +1,138 @@
+package org.javacore.time;
+
+import java.time.LocalDateTime;
+import java.time.format.DateTimeFormatter;
+
+/**
+ * 基于 JDK 8 time包的时间工具类
+ * <p/>
+ * Created by bysocket on 16/8/23.
+ */
+public class TimeUtil {
+
+	/** 默认时间格式 */
+	private static final String SHORT_DATE_PATTERN_DEFAULT				= "yyyy-MM-dd";
+	private static final String LONG_DATE_PATTERN_DEFAULT				= "yyyy-MM-dd HH:mm:ss";
+	private static final String LONG_DATE_PATTERN_WITH_MILSEC_DEFAULT	= "yyyy-MM-dd HH:mm:ss.SSS";
+
+	/** 短时间格式  : 2016-08-25 */
+	private static final String[] SHORT_DATE_PATTERN 				= { "yyyy-MM-dd",
+																		"yyyy/MM/dd",
+																		"yyyy\\MM\\dd",
+																		"yyyyMMdd"};
+	/** 长时间格式  : 2016-08-25 20:28:46 */
+	private static final String[] LONG_DATE_PATTERN 				= {"yyyy-MM-dd HH:mm:ss",
+																		"yyyy/MM/dd HH:mm:ss",
+																		"yyyy\\MM\\dd HH:mm:ss",
+																		"yyyyMMddHHmmss"};
+	/** 长时间格式 ( 带毫秒 )  : 2016-08-25 20:34:48.956 */
+	private static final String[] LONG_DATE_PATTERN_WITH_MILSEC 	= { "yyyy-MM-dd HH:mm:ss.SSS",
+																		"yyyy/MM/dd HH:mm:ss.SSS",
+																		"yyyy\\MM\\dd HH:mm:ss.SSS",
+																		"yyyyMMddHHmmssSSS"};
+
+	/**
+	 * String 转时间
+	 *
+	 * @param timeStr
+	 * @return
+	 */
+	public final static LocalDateTime parseTime(String timeStr) {
+		LocalDateTime dateTime = LocalDateTime.parse(timeStr,getDefaultDateTimeFormatter());
+		return dateTime;
+	}
+
+	/**
+	 * String 转时间
+	 *
+	 * @param timeStr
+	 * @param format 时间格式
+	 * @return
+	 */
+	public final static LocalDateTime parseTime(String timeStr, String format) {
+		LocalDateTime dateTime = LocalDateTime.parse(timeStr,getDateTimeFormatter(format));
+		return dateTime;
+	}
+
+	/**
+	 * 时间转 String
+	 *
+	 * @param time
+	 * @return
+	 */
+	public final static String parseTime(LocalDateTime time) {
+		return getDefaultDateTimeFormatter().format(time);
+	}
+
+	/**
+	 * 时间转 String
+	 *
+	 * @param time
+	 * @param format 时间格式
+	 * @return
+	 */
+	public final static String parseTime(LocalDateTime time, String format) {
+		return getDateTimeFormatter(format).format(time);
+	}
+
+	/**
+	 * 获取当前时间
+	 *
+	 * @return
+	 */
+	public final static String getCurrentDatetime() {
+		LocalDateTime now = LocalDateTime.now();
+		return getDefaultDateTimeFormatter().format(now);
+	}
+
+	/**
+	 * 获取当前时间
+	 *
+	 * @param format 时间格式
+	 * @return
+	 */
+	public final static String getCurrentDatetime(String format) {
+		LocalDateTime now = LocalDateTime.now();
+		return getDateTimeFormatter(format).format(now);
+	}
+
+	/**
+	 * 获取默认时间格式
+	 *
+	 * @return
+	 */
+	private final static DateTimeFormatter getDefaultDateTimeFormatter() {
+		return DateTimeFormatter.ofPattern(LONG_DATE_PATTERN_DEFAULT);
+	}
+
+	/**
+	 * 获取时间格式
+	 *
+	 * @param format 时间格式
+	 * @return
+	 */
+	private final static DateTimeFormatter getDateTimeFormatter(String format) {
+		return DateTimeFormatter.ofPattern(format);
+	}
+
+	public static void main(String[] args) {
+		// 当前时间
+		System.out.println(getCurrentDatetime(SHORT_DATE_PATTERN_DEFAULT));
+		System.out.println(getCurrentDatetime());
+		System.out.println(getCurrentDatetime(LONG_DATE_PATTERN_WITH_MILSEC_DEFAULT));
+
+		// 时间转 String
+		LocalDateTime dateTime = LocalDateTime.now();
+		System.out.println(parseTime(dateTime));
+
+		LocalDateTime dateTime1 = LocalDateTime.of(2016,8,25,23,10,10);
+		System.out.println(parseTime(dateTime1,LONG_DATE_PATTERN_DEFAULT));
+
+		// String 转时间
+		String dateTimeStr = "2016-08-25 23:10:10";
+		System.out.println(parseTime(dateTimeStr));
+
+		String dateTimeStr1 = "2016-08-25 23:10:10";
+		System.out.println(parseTime(dateTimeStr1,LONG_DATE_PATTERN_DEFAULT));
+	}
+}