Java: Compare two files lexicographically

Last update on April 28 2025 07:43:21 (UTC/GMT +8 hours)

Write a Java program to compare two files lexicographically.

According to Wikipedia:
In mathematics, the lexicographic or lexicographical order (also known as lexical order, dictionary order, alphabetical order or lexicographic(al) product) is a generalization of the way the alphabetical order of words is based on the alphabetical order of their component letters. This generalization consists primarily in defining a total order over the sequences (often called words in computer science) of elements of a finite totally ordered set, often called alphabet.

Sample Solution:

Java Code:

import java.io.File;
public class Exercise6 {
   public static void main(String[] args) 
   {
       String str1 = "Java exercises";
       String str2 = "Java exercises";
       String str3 = "Java examples";

       int var1 = str1.compareTo( str2 );
       System.out.println("str1 & str2 comparison: "+var1);

       int var2 = str1.compareTo( str3 );
       System.out.println("str1 & str3 comparison: "+var2);

    }
}

Sample Output:

str1 & str2 comparison: 0                                                                                     
str1 & str3 comparison: 4 

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Java program to compare two files lexicographically by reading them as streams of bytes.
• Write a Java program to sort two files based on their content’s lexicographic order and output the comparison result.
• Write a Java program to compare files lexicographically using a custom comparator that ignores case differences.
• Write a Java program to compare two text files line by line lexicographically and report the first mismatch.

Java Code Editor:

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