entityMap|blocks|key|4shgb|text|怎么样|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4mk96|BigDecimal+zero+=+BigDecimal.ZERO

Optional<Long>+addition+=+Optional.of(totalLanding.orElse(zero).add(totalSharing.orElse(zero)));|code-block|syntax|javascript|bcjhj^0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|I|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|J|9|@]|A|@]|B|$F|G]]|$2|H|4|-4|6|7|8|K|9|@]|A|@]|B|$]]]]

How about

<pre><code>BigDecimal zero = BigDecimal.ZERO

Optional&lt;Long&gt; addition = Optional.of(totalLanding.orElse(zero).add(totalSharing.orElse(zero)));
</code></pre>

entityMap|blocks|key|4jtf5|text|我们可以这样做：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|cspr4|Optional<Long>result+=+Optional.of((totalLanding+!=+null+?+totalLanding.get()+:+0L)+%2B+(totalSharing+!=+null+?+totalSharing.get()+:+0L));|code-block|syntax|javascript|euf4g^0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|I|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|J|9|@]|A|@]|B|$F|G]]|$2|H|4|-4|6|7|8|K|9|@]|A|@]|B|$]]]]

We can do like:

<pre><code>Optional&lt;Long&gt;result = Optional.of((totalLanding != null ? totalLanding.get() : 0L) + (totalSharing != null ? totalSharing.get() : 0L));
</code></pre>

entityMap|blocks|key|dld1h|text|使用Stream%25s怎么样？|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|3ekj1|Optional<Long>+total+=+Stream.of(totalLanding,totalSharing)
+++++++++++++++++++++++++++++.filter(Optional::isPresent)
+++++++++++++++++++++++++++++.map(Optional::get)
+++++++++++++++++++++++++++++.reduce(Long::sum);|code-block|syntax|javascript|2dpia|顺便说一句，我会用OptionalLong而不是Optional<Long>。|8qg3d|解决方案是类似的：|f0h4q|OptionalLong+total+=+Stream.of(totalLanding,totalSharing)
+++++++++++++++++++++++++++.filter(OptionalLong::isPresent)
+++++++++++++++++++++++++++.mapToLong(OptionalLong::getAsLong)
+++++++++++++++++++++++++++.reduce(Long::sum);|5bu0o^0|2|6|0|0|9|C|O|E|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|S|9|@$A|T|B|U|C|D]]|E|@]|F|$]]|$2|G|4|H|6|I|8|V|9|@]|E|@]|F|$J|K]]|$2|L|4|M|6|7|8|W|9|@$A|X|B|Y|C|D]|$A|Z|B|10|C|D]]|E|@]|F|$]]|$2|N|4|O|6|7|8|11|9|@]|E|@]|F|$]]|$2|P|4|Q|6|I|8|12|9|@]|E|@]|F|$J|K]]|$2|R|4|-4|6|7|8|13|9|@]|E|@]|F|$]]]]

How about using <code>Stream</code>s?

<pre><code>Optional&lt;Long&gt; total = Stream.of(totalLanding,totalSharing)
 .filter(Optional::isPresent)
 .map(Optional::get)
 .reduce(Long::sum);
</code></pre>

BTW, I'd use <code>OptionalLong</code> instead of <code>Optional&lt;Long&gt;</code>.

The solution would be similar:

<pre><code>OptionalLong total = Stream.of(totalLanding,totalSharing)
 .filter(OptionalLong::isPresent)
 .mapToLong(OptionalLong::getAsLong)
 .reduce(Long::sum);
</code></pre>

entityMap|0|type|LINK|mutability|MUTABLE|data|url|https://stackoverflow.com/questions/33942614/how-to-convert-an-optionalt-into-a-streamt|blocks|key|fm3a6|text|Java+9或更高版本：|unstyled|depth|inlineStyleRanges|entityRanges|4knie|Optional<Long>total+=+Stream.concat(
++++++++totalLanding.stream(),
++++++++totalSharing.stream())
++++.reduce(Long::sum)|code-block|syntax|javascript|30m3j|Java+8兼容变体：|ajkan|Optional<Long>total+=+Stream.concat(
++++++++totalLanding.map(Stream::of).orElseGet(Stream::empty),
++++++++totalSharing.map(Stream::of).orElseGet(Stream::empty))
++++.reduce(Long::sum)|bjot4|或者更好的做法是提取.map(Stream::of).orElseGet(Stream::empty)作为实用方法并重用。或其他变体在这里：How+to+convert+an+Optional+into+a+Stream?|offset|length|style|CODE|vtn3^0|0|0|0|0|A|15|1Y|15|0|0^^$0|$1|$2|3|4|5|6|$7|8]]]|9|@$A|B|C|D|2|E|F|Y|G|@]|H|@]|6|$]]|$A|I|C|J|2|K|F|Z|G|@]|H|@]|6|$L|M]]|$A|N|C|O|2|E|F|10|G|@]|H|@]|6|$]]|$A|P|C|Q|2|K|F|11|G|@]|H|@]|6|$L|M]]|$A|R|C|S|2|E|F|12|G|@$T|13|U|14|V|W]]|H|@$T|15|U|16|A|17]]|6|$]]|$A|X|C|-4|2|E|F|18|G|@]|H|@]|6|$]]]]

Java 9 or newer:

<pre><code>Optional&lt;Long&gt;total = Stream.concat(
 totalLanding.stream(),
 totalSharing.stream())
 .reduce(Long::sum)
</code></pre>

Java 8 compatible variant:

<pre><code>Optional&lt;Long&gt;total = Stream.concat(
 totalLanding.map(Stream::of).orElseGet(Stream::empty),
 totalSharing.map(Stream::of).orElseGet(Stream::empty))
 .reduce(Long::sum)
</code></pre>

Or better to extract the <code>.map(Stream::of).orElseGet(Stream::empty)</code> as a utility method and reuse. Or other variants here: <a href="https://stackoverflow.com/questions/33942614/how-to-convert-an-optionalt-into-a-streamt">How to convert an Optional&lt;T&gt; into a Stream&lt;T&gt;?</a>

entityMap|blocks|key|frne|text|这应该适用于Java+8：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|dl1s4|Optional<Long>+total+=+totalLanding.map(x+->+x+%2B+totalSharing.orElse(0L))
++++++++.map(Optional::of)+++//+wrap+it+twice+for+the+next+line+to+find+an+Optional+inside
++++++++.orElse(totalSharing);|code-block|syntax|javascript|aa5sm^0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|I|9|@]|A|@]|B|$]]|$2|C|4|D|6|E|8|J|9|@]|A|@]|B|$F|G]]|$2|H|4|-4|6|7|8|K|9|@]|A|@]|B|$]]]]

This should work with Java 8:

<pre><code>Optional&lt;Long&gt; total = totalLanding.map(x -&gt; x + totalSharing.orElse(0L))
 .map(Optional::of) // wrap it twice for the next line to find an Optional inside
 .orElse(totalSharing);
</code></pre>

<pre><code>Optional&lt;Long&gt;totalLanding= ....(get it from somewhere);
Optional&lt;Long&gt;totalSharing = ...(get it from somewhere);
</code></pre>

I want to do something like this not syntactically but logically

<pre><code>Optional&lt;Long&gt;total = totalLanding+totalSharing;
</code></pre>

Such that if both are empty then total should be empty if one of them has the value then total should have that value is both of them have the value then they should get added and stored in total

How to add two Optional<Long> in java

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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Optional<Long>totalLanding= ....(get it from somewhere);Optional<Long>totalSharing = ...(get it from somewhere); 我想做这样的事情，不是语法上的，而是逻辑上的 Optional<Long>total = t...

问如何在java中添加两个Optional<Long>
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问如何在java中添加两个Optional<Long>EN