How to Use the 'Each' Method In Groovy?

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The 'each' method in Groovy is used to iterate over a collection of elements such as a list, map, or range. It takes a closure as an argument and executes that closure for each element in the collection.


You can use 'each' to perform actions on each element in the collection, such as printing out the values or performing calculations. For example, you can loop through a list of numbers and print out each number like this:


def numbers = [1, 2, 3, 4, 5] numbers.each { println it }


You can also use the 'each' method to iterate over a map and access both the key and value in the closure. For example, you can loop through a map of names and ages and print out each name and age like this:


def ages = ['John': 30, 'Mary': 25, 'Tom': 35] ages.each { name, age -> println "$name is $age years old" }


Overall, the 'each' method in Groovy is a convenient and powerful way to iterate over collections and perform actions on each element.

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How to use the 'each' method recursively in Groovy for nested collections?

To use the each method recursively in Groovy for nested collections, you can create a recursive function that iterates over each element in the collection and, if the element is also a collection, calls the function recursively on that sub-collection. Here's an example:

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def recursiveEach = { collection ->
    collection.each { element ->
        if (element instanceof Collection) {
            recursiveEach(element)
        } else {
            println element
        }
    }
}

def nestedCollection = [[1, 2], [3, 4], 5, [6, [7, 8, 9]]]
recursiveEach(nestedCollection)


In this example, the recursiveEach function takes a collection as input and iterates over each element. If the element is also a collection, it calls itself recursively on that sub-collection. If the element is not a collection, it simply prints the element.


You can modify the logic inside the each closure to perform different operations on each element in the nested collections.


What is the syntax of the 'each' method in Groovy?

In Groovy, the 'each' method is used to iterate over a collection and execute a closure for each element in the collection. The syntax of the 'each' method is as follows:

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collection.each { item ->
    // code to be executed for each element
}


In this syntax:

  • 'collection' is the collection that needs to be iterated over.
  • 'item' is a variable that represents each element in the collection during iteration.
  • The code block within the curly braces is the closure that will be executed for each element in the collection.


What is the difference between 'each' and 'eachWithIndex' methods in Groovy?

In Groovy, the each method is used to iterate over each element in a collection and apply a closure to it. This method only passes the value of the element to the closure.


On the other hand, the eachWithIndex method is similar to the each method, but it also passes the index of the element to the closure along with the value. This can be useful if you need access to both the index and the value of the element during the iteration.

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