Question

(Tokenizing and Comparing Strings) Write an application that reads a line of text, tokenizes it using space characters as delimiters and outputs only those words ending with the letters "ED".

Short answer

Read and split the input text, filter words ending with 'ED', and output them.

Step-by-step solution

- Read Input Text

Prompt the user to input a line of text and store this text into a variable for future processing.

- Tokenize the Text

Split the input text into tokens (words) by using space characters as delimiters. This can typically be done by using the string split() method or similar functionality, depending on the programming language.

- Initialize the Result Collection

Before checking the tokens, initialize an empty collection (like a list or an array) to store words that end with 'ED'.

- Identify and Store Words Ending with 'ED'

Loop through the list of tokens and for each token, check if it ends with the letters 'ED'. If it does, add it to the previously initialized result collection.

- Output the Selected Words

Finally, output the collection of words that end with 'ED'. This could be done by printing each word separately, or by creating a string of these words and then printing that string.

Key concepts

Java Programming

Java is a versatile and powerful programming language that allows developers to create robust, multi-platform applications. When it comes to manipulating text or strings, Java provides a rich set of tools and methods that make these tasks straightforward. For example, to tackle the exercise at hand, one would start by utilizing Java's I/O capabilities to read user input.

In Java, the Scanner class can be used to read input from the console, and this is what is typically the first step in processing text. Once the input is obtained, Java's String class comes into play. This class includes various methods such as split() to divide a string into parts or 'tokens', based upon specified delimiters like spaces.

Understanding the flow of Java I/O operations and familiarity with the String class methods are fundamental for text processing tasks such as the given exercise.

String Manipulation

String manipulation encompasses a wide array of actions you can perform on text data, from altering its content to analyzing its structure. In Java, string manipulation is commonly handled with methods from the String class. Following the textbook exercise process, once the input text is tokenized using the split() method, individual tokens can be analyzed.

The method endsWith() is specifically useful for the problem at hand. It checks whether a given string concludes with a particular set of characters—in this case, 'ED'. For our exercise, iterating over each token and applying this method allows us to efficiently filter out only those words that meet our criteria.

It's essential to remember that strings in Java are immutable; any method that seems to modify a string actually creates a new one. Hence, for memory optimization, using a StringBuilder for constructing the output can be a wise choice if concatenation operations are required.

Text Processing

Text processing goes beyond simple manipulation; it involves analyzing and transforming text data to achieve a particular outcome, such as formatting or information extraction. This process requires a keen understanding of the data format and the operations necessary to parse and modify it.

In our exercise, text processing begins with tokenization, which is converting a string into an array of substrings using delimiters—the spaces in our text. Once tokenized, the next step is to process these tokens based on a specific condition, like those ending with 'ED'. This selection criteria reflects a simple form of pattern matching, which is a central aspect of text processing.

After identifying the necessary tokens, the results must be outputted. This might involve assembling the tokens back into a formatted string or simply iterating over the collection to print them. Regardless of the approach, the output should be clear and concise, reflecting the programmer's intent to make accessible the fruits of their text processing.