如何创建一个单独的表达式来显示两个日期之间的时间差异，比如年、月、天、小时、分钟、秒

How can I create a single jasper report JRExpression that visualize the difference between two java.util.Date in format yy year(s) month(s) dd day(s), hh hour(s), mm minute(s), ss second(s)

如何创建一个jasper report JRExpression，该JRExpression是两个java.util之间的差异。日期格式yy年(s)月日(s)， hh小时(s)， mm分钟(s)， s秒(s)

java.util.Date startDate
java.util.Date endDate

A JRExpression is a single line where variable declaration is not allowed, however you may use conditional statements using syntax boolean ? yes:no, for you who are not familiar imagine one line of System.out.println();

JRExpression是哪一行不允许变量声明，但是您可以使用语法布尔的条件语句?是的，不熟悉的同学可以想象一下系统的一行。输出。println();

Example of desired output (if you have a nice solution remove description of unit when not present and consider singular/plural but this is not necessary if it's a serie of if statements):

想要输出的例子(如果你有一个很好的解决方案，在不存在的情况下，删除单位的描述，并考虑单数/复数形式，但如果它是一种if语句，这是不必要的):

2 years, 8 months, 12 days, 2 hours, 53 minutes, 10 s

2年，8个月，12天，2小时，53分钟，10秒。

1 hour, 1 minute

1小时1分钟

both Feb 2- Mar 4 and Mar 4 - April 6 are "1 month, 2 days", daylight savings however can be ignored - thanks @Affe

2月2日- 3月4日和4月4日- 4月6日都是“1个月，2天”，但是可以忽略日光节约——谢谢@Affe

Additional requirements:

附加要求:

Only jasper report dependencies may be used (joda is not included).
只能使用jasper报表依赖项(不包括joda)。
Preferable jdk 1.7 or less (1.8 is accepted if this is only solution)
更好的jdk 1.7或更少(如果这是唯一的解决方案，1.8将被接受)

There is no need to format the answer as jasper report expression it can be a simple System.out.println code (I'm happy to edit your answer later to also add the jasper report expression code). Example

不需要将答案格式化为jasper report expression它可以是一个简单的System.out。println代码(我很高兴稍后编辑您的答案，并添加jasper报表代码)。例子

((endDate.getTime()-startDate.getTime()) / (60 * 60 * 1000)) % 24 + " hour(s), " +  
((endDate.getTime()-startDate.getTime()) / (60 * 1000)) % 60 + " minute(s)"

What have I tried:

我尝试:

I answer multiple question in the jasper report section of SO, and this question is common in report generation. I would prefer a good answer from the java section that I can link rather then passing my code on this issue (that I would only know to solve partially as example)

我在SO的jasper report部分回答了多个问题，这个问题在报告生成中很常见。我希望java部分给出一个好的答案，我可以链接它，而不是在这个问题上传递我的代码(作为示例，我只知道要解决部分问题)

This is an example on question in jasper-report: Calculating Time and Date difference

这是jasper-report中的一个问题示例:计算时间和日期差异

Some reference code:

参考代码:

Calculate date/time difference in java

计算java中的日期/时间差异。

How to find the duration of difference between two dates in java?

如何在java中找到两个日期之间的差异持续时间?

For you that are familiar to jasper report I don't want to use the variable declaration since this would invalidate the solution if user need to use it on parameters.

对于您熟悉的jasper报告，我不想使用变量声明，因为如果用户需要在参数上使用它，将会使解决方案无效。

1 个解决方案

#1

The Calendar API cannot be directly be used for this problem: every operation would require multiple lines since the interesting methods are void returning and can't be chained.

不能直接使用Calendar API来解决这个问题:每个操作都需要多行，因为有趣的方法是无效返回的，不能链接。

This is a very big stretch, but, as listed in the dependencies of JasperReports, there is org.codehaus.castor:castor-xml:1.3.3 which depends itself on commons-lang:commons-lang:2.6. We therefore can make use of the DurationFormatUtils.formatPeriod(startMillis, endMillis, format) method, which is present in commons-lang. The format String to use here would be

这是一个很大的扩展，但是，正如在JasperReports的依赖项中所列，有org.code .castor:castor-xml:1.3.3，它依赖于common -lang:common -lang:2.6。因此，我们可以利用DurationFormatUtils。formatPeriod(startMillis, endMillis, format)方法，它在common -lang中出现。这里要使用的格式字符串是

"y' years 'M' months 'd' days 'H' hours 'm' minutes 's' seconds'"

which would print the wanted String. Care must still be taken: this will include 0s (like "0 months") and will also have incorrect pluralization (like "1 months").

打印需要的字符串。仍然要小心:这将包括0(如“0个月”)，并且会有错误的多元化(如“1个月”)。

We can use the regular expression "(?<!\\d)0 (\\w+) ?" to remove all the 0s for the String. This regex matches any 0, not preceded by a digit (we don't want to match 10 for example), followed by one or more word characters and optionally followed by a space.
我们可以使用正则表达式“(?
Then, we can use the regular expression "(?<!\\d)1 (\\w+)s" to match every occurence of "1 ...s" and replace it with "1 ..." to have proper pluralization. This regular expression matches any 1, not preceded by a digit, followed by one or more word characters (captured in a group) ending with an s; it would be replaced with "1 $1", i.e. 1 followed by the value captured.
然后，我们可以使用正则表达式“(?

Example:

例子:

System.out.println(
    org.apache.commons.lang.time.DurationFormatUtils.formatPeriod(
            startDate.getTime(), 
            endDate.getTime(), 
            "y' years 'M' months 'd' days 'H' hours 'm' minutes 's' seconds'"
    )
    .replaceAll("(?<!\\d)0 (\\w+) ?", "")
    .replaceAll("(?<!\\d)1 (\\w+)s", "1 $1")
);

All this can be done with Java 7 or lower.

所有这些都可以用Java 7或更低的方式完成。

In a JasperReports, this would be an example:

在JasperReports中，这是一个例子:

<?xml version="1.0" encoding="UTF-8"?>
<!-- Created with Jaspersoft Studio version 6.2.1.final using JasperReports Library version 6.2.1 -->
<jasperReport xmlns="http://jasperreports.sourceforge.net/jasperreports" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://jasperreports.sourceforge.net/jasperreports jasperreports.sourceforge.net/…" name="Blank_A4" pageWidth="595" pageHeight="842" whenNoDataType="AllSectionsNoDetail" columnWidth="555" leftMargin="20" rightMargin="20" topMargin="20" bottomMargin="20" uuid="f067f2c4-395f-4669-9fda-4fe81cc59227">
  <property name="com.jaspersoft.studio.data.defaultdataadapter" value="One Empty Record"/>
  <parameter name="dateStart" class="java.util.Date" isForPrompting="false">
    <defaultValueExpression><![CDATA[new java.util.Date(1)]]></defaultValueExpression>
  </parameter>
  <parameter name="dateEnd" class="java.util.Date" isForPrompting="false">
    <defaultValueExpression><![CDATA[new java.util.Date()]]></defaultValueExpression>
  </parameter>
  <queryString><![CDATA[]]></queryString>
  <title>
    <band height="43" splitType="Stretch">
      <textField>
        <reportElement x="0" y="0" width="560" height="30" uuid="cc03531c-2983-4f9a-9619-2826ed92760e"/>
        <textFieldExpression><![CDATA[org.apache.commons.lang.time.DurationFormatUtils.formatPeriod($P{dateStart}.getTime(),$P{dateEnd}.getTime(),"y' years 'M' months 'd' days 'H' hours 'm' minutes 's' seconds'").replaceAll("(?<!\\d)0 (\\w+) ?", "").replaceAll("(?<!\\d)1 (\\w+)s", "1 $1")]]></textFieldExpression>
      </textField>
    </band>
  </title>
</jasperReport>

With the output being:

输出是:

If the above looks too fragile (because of the explicit dependency towards commons-lang that could not be there for all JasperReports version), there is another possible solution using the Java Time API introduced in Java 8.

如果上面的内容看起来太脆弱(由于对common -lang的显式依赖，不能用于所有JasperReports版本)，那么使用Java 8中引入的Java Time API还有另一种可能的解决方案。

This is horrible (I don't think there is a simpler way), but the output is exactly the same as above, where start and end are both LocalDateTime objects:

这很可怕(我不认为有更简单的方法)，但是输出结果与上面完全相同，其中start和end都是LocalDateTime对象:

System.out.println((
    ChronoUnit.YEARS.between(start, end) + " years " +
    ChronoUnit.MONTHS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)), end) + " months " +
    ChronoUnit.DAYS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)).plusMonths(ChronoUnit.MONTHS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)), end)), end) + " days " +
    ChronoUnit.HOURS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)).plusMonths(ChronoUnit.MONTHS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)), end)).plusDays(ChronoUnit.DAYS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)).plusMonths(ChronoUnit.MONTHS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)), end)), end)), end) + " hours " +
    ChronoUnit.MINUTES.between(start.plusYears(ChronoUnit.YEARS.between(start, end)).plusMonths(ChronoUnit.MONTHS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)), end)).plusDays(ChronoUnit.DAYS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)).plusMonths(ChronoUnit.MONTHS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)), end)), end)).plusHours(ChronoUnit.HOURS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)).plusMonths(ChronoUnit.MONTHS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)), end)).plusDays(ChronoUnit.DAYS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)).plusMonths(ChronoUnit.MONTHS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)), end)), end)), end)), end) + " minutes " +
    ChronoUnit.SECONDS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)).plusMonths(ChronoUnit.MONTHS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)), end)).plusDays(ChronoUnit.DAYS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)).plusMonths(ChronoUnit.MONTHS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)), end)), end)).plusHours(ChronoUnit.HOURS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)).plusMonths(ChronoUnit.MONTHS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)), end)).plusDays(ChronoUnit.DAYS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)).plusMonths(ChronoUnit.MONTHS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)), end)), end)), end)).plusMinutes(ChronoUnit.MINUTES.between(start.plusYears(ChronoUnit.YEARS.between(start, end)).plusMonths(ChronoUnit.MONTHS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)), end)).plusDays(ChronoUnit.DAYS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)).plusMonths(ChronoUnit.MONTHS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)), end)), end)).plusHours(ChronoUnit.HOURS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)).plusMonths(ChronoUnit.MONTHS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)), end)).plusDays(ChronoUnit.DAYS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)).plusMonths(ChronoUnit.MONTHS.between(start.plusYears(ChronoUnit.YEARS.between(start, end)), end)), end)), end)), end)), end) + " seconds"
    )
    .replaceAll("(?<!\\d)0 (\\w+) ?", "")
    .replaceAll("(?<!\\d)1 (\\w+)s", "1 $1")
);

#1