Let's consider that we have a <code>HashMap</code> of the following type:
<pre><code>Map&lt;String, List&lt;String&gt;&gt; myMap = new HashMap&lt;&gt;();
</code></pre>We want to iterate through the entire hashmap and get all the values to a single <code>List&lt;String&gt;</code>. There could be many ways to solve this problem in Java but let's take a look at a couple of simpler ways.
The first way is to use the <code>values</code> method:
<pre><code>List&lt;String&gt; myList = new ArrayList&lt;&gt;(map.values());
</code></pre>Since most of us are already using JDK &gt;=8 we can also use the following but that's a little more verbose <code>:)</code>:
<pre><code>List&lt;String&gt; myList = map.values().stream().collect(Collectors.toList());
</code></pre>

Let's consider that we have a `HashMap` of the following type:

```
Map<String, List<String>> myMap = new HashMap<>();
``` 

We want to iterate through the entire hashmap and get all the values to a single `List<String>`. There could be many ways to solve this problem in Java but let's take a look at a couple of simpler ways.

The first way is to use the `values` method:
```
List<String> myList = new ArrayList<>(map.values());
```

Since most of us are already using JDK >=8 we can also use the following but that's a little more verbose `:)`:

```
List<String> myList = map.values().stream().collect(Collectors.toList());
```

How to convert values in a HashMap to a List<String>