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From the javadoc for
[`java.util.stream: Non-interference`](https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/stream/package-summary.html#NonInterference):
> Accordingly, behavioral parameters in stream pipelines whose source might not
> be concurrent should never modify the stream's data source. A behavioral
> parameter is said to interfere with a non-concurrent data source if it
> modifies, or causes to be modified, the stream's data source. The need for
> non-interference applies to all pipelines, not just parallel ones. Unless the
> stream source is concurrent, modifying a stream's data source during execution
> hg of a stream pipeline can cause exceptions, incorrect answers, or
> nonconformant behavior.
That is, prefer this:
```java
mutableValues.stream()
.filter(x -> x < 5)
.collect(Collectors.toList()) // Terminate stream before source modification.
.forEach(mutableValues::remove);
```
to this:
```java
mutableValues.stream()
.filter(x -> x < 5)
.forEach(mutableValues::remove);
```
|
