In Java programming, a string is an object that represents a sequence of characters. Strings are created and manipulated using the String class. A string can be created in Java using either a string literal or a new keyword. StringBuffer and StringBuilder implement the CharSequence in Java to generate new strings. Java String class has many methods to perform operations on strings such as concat(), compare(), split(), equals(), length(), replace(), matches(), trim(), compareTo(), substring(), intern() etc.
The following section contains various programs on strings, string operations, string matching, approximate string matching, and encryption algorithms. Each sample program includes a program description, Java code, and program output. All examples have been compiled and tested on Windows and Linux systems.
Here is the listing of Java programming examples on Strings:
- Java Programs on String Operations
- Java Programs on Strings
- Java Programs on String Matching
- Java Programs on Approximate String Matching
- Java Programs on Cryptography
- Java Programs on Longest Common SubString/SubSequence
| Program | Description |
|---|---|
| String Concatenation in Java | Java Program to Concatenate Two Strings Input: Enter First String: Hello Enter Second String: World Output: Hello World |
| Remove Characters from Input String in Java | Java Program to Remove Characters from the Input String which are Present in the Mask String Input: Enter String: Practice Java String Programs Enter Mask String: abc Output: Prtie Jv String Progrms |
| Delete Adjacent Duplicates from String in Java | Java Program to Remove All Adjacent Duplicates from String Input: String: ABBCCCD Output: ACD |
| Reverse Each Word in a String in Java | Java Program to Reverse Each Word in a String Input: String: Java Programs on String Output: avaj smargorp no gnirts |
| Convert String to Integer Array in Java | Java Program to Convert a String to an Integer Array Input: Enter the string: abc pqr xyz Output: -1 -1 -1 |
| Program | Description |
|---|---|
| Largest & Smallest Word in a String in Java | Java Program to Find the Largest and Smallest Word in a String Input: Enter String: String Programs in Java Output: The largest and smallest word is “Programs” and “in” |
| First Non Repeating Character in a String in Java | Java Program to Find the First Non-repeated Character in a String Input: Enter String: Welcome to Sanfoundry Output: First Non-Repeating Character is W |
| Length of Longest Repeating Subsequence in Java | Java Program to Find the Length of Longest Repeating Sequence in a String |
| Longest Common Substring in Java | Java Program to Find Length of Longest Common Substring |
| Print Longest Substring without Repeating Characters in Java | Java Program to Find the Longest SubString Without Any Repeated Characters |
| Count Unique Words from a String in Java | Java Program to Count the Number of Unique Words Input: Enter String: Java is great C++ is also great Output: Total number of unique words are 3 |
| Count Vowels, Uppercase, Lowercase & Special Characters from a String in Java | Java Program to Find the First Capital Letter/Small Letter/Vowel/Consonant/Number/Whitespace/Special Character in a Given String |
| Permutation of a String in Java | Java Program to Permute All Letters of an Input String |
| Check if Two Strings are Permutation of Each Other in Java | Java Program to Check if Two Strings are Cyclic Permutations of Each Other |
| String Palindrome Program in Java | Java Program to Check if a Given String is Palindrome Input: Enter String: NeveroddorEVen Output: The string is palindrome |
| Anagram Palindrome in Java | Java Program to Check if Any Anagram of a String is Palindrome or Not |
| Switch Case String in Java | Java Program to Implement Switch Statement on Strings |
| Grep, Egrep & Fgrep in Java | Java Program to Implement Grep, Egrep and Fgrep Commands |
| Program | Description |
|---|---|
| Naive String Matching in Java | Java Program to Perform Naive String Matching |
| Aho-Corasick Algorithm in Java | Java Program to Implement Aho Corasick Algorithm for Pattern Searching |
| Rabin Karp String Matching Algorithm in Java | Java Program to Implement Rabin-Karp Method for Pattern Searching |
| Manacher Algorithm in Java | Java Program to Implement Manacher Algorithm |
| Wagner Fischer Algorithm in Java | Java Program to Implement Wagner Fischer Algorithm |
| String Matching Using Library in Java | Java Program to Perform String Matching Using String Library |
| String Matching Using Vectors in Java | Java Program to Perform String Matching Using Vectors |
| String Search Algorithm in Java | Java Program to Implement String Search Algorithm for Short Text Sizes |
| Repeated Search Pattern in Java | Java Program to Repeatedly Search the Same Text |
| Program | Description |
|---|---|
| Approximate String Matching using DP in Java | Java Program to Solve Approximate String Matching using Dynamic Programming |
| Online String Matching using Wagner & Fisher in Java | Java Program to Implement Wagner and Fisher Algorithm for Online String Matching |
| Levenshtein Distance Computing Algorithm in Java | Java Program to Implement Levenshtein Distance Computing Algorithm |
| Program | Description |
|---|---|
| Monoalphabetic Cypher in Java | Java Program to Implement the Monoalphabetic Cipher Input: Enter the message: Sanfoundry Output: Encrypted message: LQFYGXFRKN; Decrypted message: sanfoundry |
| Caesar Cipher in Java | Java Program to Implement Caesar Cipher Input: Enter the String for Encryption: Sanfoundry Output: vdqirxqgub |
| Vigenere Cipher in Java | Java Program to Implement the Vigenere Cipher |
| Hill Cipher in Java | Java Program to Implement the Hill Cipher |
| Affine Cipher in Java | Java Program to Implement Affine Cipher |
| Playfair Cipher Encryption Program in Java | Java Program to Encrypt Message using Playfair Cipher |
| Playfair Cipher Decryption Program in Java | Java Program to Decrypt Message using Playfair Cipher |
| One Time Pad Algorithm in Java | Java Program to Implement the One Time Pad Algorithm |
| RSA Algorithm in Java | Java Program to Implement the RSA Algorithm |
| MD5 Algorithm in Java | Java Program to Implement the MD5 Algorithm |
| Transposition Technique Program in Java | Java Program to Perform Cryptography using Transposition Technique Input: Encrypted Message: f*o*n*ayn*d*Sru* Output: Decrypted Message: Sanfoundry |
| Checksum Program in Java | Java Program to Implement the Checksum Method for Small String Messages |
| Program | Description |
|---|---|
| Longest Increasing Subsequence in Java | Java Program to Find the Longest Increasing Subsequence |
| Longest Common Subsequence Algorithm in Java | Java Program to Implement Longest Common Subsequence Algorithm |
| Longest Common Subsequence in Java | Java Program to Find the Longest Subsequence Common to All Sequences in a Set of Sequences |
