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# Keys
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<br>
Takes a collection of key-value pairs, and returns the key of each element.

## Examples
**Example**

```java
PCollection<KV<String, Integer>> keyValuePairs = /* ... */;
PCollection<String> keys = keyValuePairs.apply(Keys.create());
```

## Related transforms 
* [KvSwap]({{ site.baseurl }}/documentation/transforms/java/elementwise/kvswap) swaps key-value pair values.
* [Values]({{ site.baseurl }}/documentation/transforms/java/elementwise/values) for extracting the value of each element.
* [WithKeys]({{ site.baseurl }}/documentation/transforms/java/elementwise/withkeys) for adding a key to each element.