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In this solution, we're going to finish part four.

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The Geter receives a string and from the string in each the return, the key that the caller is interested

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in, in the article, I showed you four different ways to accomplish this task.

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I'm going to start off with the most elegant way anyway's.

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We can run through every key and a hash map as a key set this scoreboard key set and we're going to

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run the key, sat through a stream pipeline stream and recommit.

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A stream is a sequence of elements that we can run through a pipeline of functions.

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And the first function, the first operation is going to be filter filter in effect, filters every

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element that matches a predicates.

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The lambda expression receives every key as a parameter and the arrow key points to a condition that

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determines the filtering process.

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And we're going to filter out the key whose house name matches the one being passed in.

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At this point, there should only be one key, so we'll say find first and return the key that it finds.

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And if it can't find anything, we'll return No.

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So that's one way you can do it.

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If you're satisfied with the way you can feel free to skip to this timestamp.

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Otherwise, I can show you the three other approaches.

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OK, I'm going to use the same pipeline, but instead of running through each key in the hash map,

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I'll run through every entry.

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And now we're getting errors because the lambda expression receives each entry.

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And from the entry, we'll get the key.

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And now we're filtering the entry that matches this predicate, OK, and sends the stream is now a sequence

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of entries, find first returns, the first entry that it finds, but we need to return the key.

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So at the end, we need to say get key.

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OK, and now the main takeaway is that a hash map has entries, each entry contains a key and a value,

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and we can choose to run through every key or every entry.

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Can I will change up the pipeline, put this back as a Keystart?

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You can remove the jet ski at the end because now the stream is already a sequence of keys and we can

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use a different terminal operation collects and the collector we're going to choose from the list of

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collectors is to list.

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We expect to list only have one filtered key, so we're going to grab the element at index zero.

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That's another way to do things.

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All right, another final thing we can do is run through every entry instead.

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And using the same pipeline, the list should now contain only one elements here, we're indexing that

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entry and we're going to grab that entry's key.

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That's what we need to return to.

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The main takeaway is that there are so many ways to accomplish the same thing.

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We could have even used the loop to run through every entry in the entry set or every key in the key

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set.

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But obviously a pipeline is much cleaner and more concise.

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All right, I'm going to go back to using the first pipeline find first.

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And run through each key in the key set, because I think it's the most elegant approach.

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All right, let's test it out, let me clean up here.

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And get the team Gryffindor.

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And beautiful.

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Our final task was to create a static variable called game count static int game count.

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And game count is going to count the number of games played.

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The reason this variable is static is because it doesn't make sense for a game object to have a field

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called game count.

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The game count is the same across all objects.

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The number of games played relates to the class, not objects of the class.

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And we want to be able to access this variable directly from the class type anyways every time a new

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game is played.

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In other words, every time a new game object is created, add one to the count.

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OK, now I'm going to create three objects of the game class.

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Change the variable names.

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And print the game counts.

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OK, since it's in a different folder, I need the visibility to be explicitly public.

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OK, and we got three cool.

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But like fields, this static variable should be private because we don't want the caller to have access

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to it.

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This is a security risk because the caller may update it by mistake.

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So we'll need to make this private's.

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And create a GETER, which I can use autocomplete.

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And IT autocomplete, a static getter cool, the getter returns a copy of the variable, its value.

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And now we can call the static method from meina.

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And everything works perfectly.

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Our variable effectively keeps track of how many games are played.

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We're actually not going to end up using game count as part of the final simulation.

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But I just wanted you to get some more practice with static variables.