我們還是在一個例子中來看上述各個類的用法吧：
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package
sean.study.jakarta.commons.lang;
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import
java.util.Calendar;
import
java.util.Date;
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import
org.apache.commons.lang.StringUtils;
import
org.apache.commons.lang.time.DateFormatUtils;
import
org.apache.commons.lang.time.DateUtils;
import
org.apache.commons.lang.time.FastDateFormat;
import
org.apache.commons.lang.time.StopWatch;
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public
class
DateTimeUsage {
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???
public
static
void
main(String[] args) {
??????? demoDateUtils();
??????? demoStopWatch();
??? }
???
???
public
static
void
demoDateUtils() {
??????? System.out.println(StringUtils.center(" demoDateUtils ", 30, "="));
??????? Date date = new Date();
??????? String isoDateTime = DateFormatUtils.ISO_DATETIME_FORMAT.format(date);
??????? String isoTime = DateFormatUtils.ISO_TIME_NO_T_FORMAT.format(date);
??????? FastDateFormat fdf = FastDateFormat.getInstance("yyyy-MM");
??????? String customDateTime = fdf.format(date);
??????? System.out.println("ISO_DATETIME_FORMAT: " + isoDateTime);
??????? System.out.println("ISO_TIME_NO_T_FORMAT: " + isoTime);
??????? System.out.println("Custom FastDateFormat: " + customDateTime);
??????? System.out.println("Default format: " + date);
??????? System.out.println("Round HOUR: " + DateUtils.round(date, Calendar.HOUR));
??????? System.out.println("Truncate HOUR: " + DateUtils.truncate(date, Calendar.HOUR));
??????? System.out.println();
??? }
???
???
public
static
void
demoStopWatch() {
??????? System.out.println(StringUtils.center(" demoStopWatch ", 30, "="));
??????? StopWatch sw = new StopWatch();
??????? sw.start();
??????? operationA();
??????? sw.stop();
??????? System.out.println("operationA used " + sw.getTime() + " milliseconds.");
??????? System.out.println();
??? }
???
???
public
static
void
operationA() {
???????
try
{
??????????? Thread.sleep(999);
??????? }
???????
catch
(InterruptedException e) {
??????????? // do nothing
??????? }
??? }
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}
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以下是運行結果：
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======= demoDateUtils ========
ISO_DATETIME_FORMAT: 2005-08-01T12:41:51
ISO_TIME_NO_T_FORMAT: 12:41:51
Custom FastDateFormat: 2005-08
Default format: Mon Aug 01 12:41:51 CST 2005
Round HOUR: Mon Aug 01 13:00:00 CST 2005
Truncate HOUR: Mon Aug 01 12:00:00 CST 2005
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======= demoStopWatch ========
operationA used 1000 milliseconds.