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How to clone a HashMap in Kotlin

How to clone a HashMap in Kotlin.

Here's a step-by-step tutorial on how to clone a HashMap in Kotlin:

Step 1: Create a HashMap​

To begin, let's create a HashMap that we want to clone. We can do this by using the mutableMapOf() function and adding some key-value pairs to it. Here's an example:

val originalHashMap = mutableMapOf(
    "key1" to "value1",
    "key2" to "value2",
    "key3" to "value3"
)

Step 2: Clone the HashMap using the toMap() function​

Kotlin provides a convenient method called toMap() that can be used to clone a HashMap. This function creates a new read-only Map with the same key-value pairs as the original HashMap. Here's how you can use it:

val clonedHashMap = originalHashMap.toMap()

In the above code, originalHashMap.toMap() creates a new read-only Map that is assigned to the clonedHashMap variable.

Step 3: Verify the cloning​

To ensure that the cloning was successful, you can print the contents of both the original and cloned HashMaps. Here's an example:

println("Original HashMap: $originalHashMap")
println("Cloned HashMap: $clonedHashMap")

When you run this code, you should see the key-value pairs of both the original and cloned HashMaps printed to the console.

Step 4: Modify the cloned HashMap​

If you modify the cloned HashMap, the changes should not affect the original HashMap. This is because the cloned HashMap is a separate object with its own set of key-value pairs. Let's demonstrate this with an example:

clonedHashMap["key1"] = "newValue"

In the above code, we modify the value associated with the key "key1" in the cloned HashMap.

Step 5: Verify the modifications​

To verify that the modifications made to the cloned HashMap did not affect the original HashMap, you can print their contents again. Here's an example:

println("Original HashMap after modification: $originalHashMap")
println("Cloned HashMap after modification: $clonedHashMap")

When you run this code, you should see that the value associated with "key1" has changed in the cloned HashMap, but remains the same in the original HashMap.

And that's it! You have successfully cloned a HashMap in Kotlin. Remember that cloning a HashMap using the toMap() function creates a new read-only Map, so any modifications need to be made to a mutable Map if you want to change its contents.