Merge pull request #236 from Mcbencrafter/main

[Snippets] Added String Manipulation Snippets for java

Author: Mathys-Gasnier

snippets/java/string-manipulation/ascii-to-string.md

@@ -0,0 +1,23 @@
+---
+title: Ascii To String
+description: Converts a list of ascii numbers into a string
+author: Mcbencrafter
+tags: string,ascii,encoding,decode,conversion
+---
+
+```java
+import java.util.List;
+
+public static String asciiToString(List<Integer> asciiCodes) {
+    StringBuilder text = new StringBuilder();
+
+    for (int asciiCode : asciiCodes) {
+        text.append((char) asciiCode);
+    }
+
+    return text.toString();
+}
+
+// Usage:
+System.out.println(asciiToString(List.of(104, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100))); // "hello world"
+```

snippets/java/string-manipulation/camelcase-to-snake-case.md

@@ -0,0 +1,15 @@
+---
+title: camelCase to snake_case
+description: Converts a camelCase string into snake_case
+author: Mcbencrafter
+tags: string,conversion,camel-case,snake-case
+---
+
+```java
+public static String camelToSnake(String camelCase) {
+    return camelCase.replaceAll("([a-z])([A-Z])", "$1_$2").toLowerCase();
+}
+
+// Usage:
+System.out.println(camelToSnake("helloWorld")); // "hello_world"
+```

snippets/java/string-manipulation/capitalize-words.md

@@ -0,0 +1,27 @@
+---
+title: Capitalize Words
+description: Capitalizes the first letter of each word in a string
+author: Mcbencrafter
+tags: string,capitalize,words
+---
+
+```java
+public static String capitalizeWords(String text) {
+    String[] words = text.split("(?<=\\S)(?=\\s+)|(?<=\\s+)(?=\\S)"); // this is needed to preserve spaces (text.split(" ") would remove multiple spaces)
+    StringBuilder capitalizedText = new StringBuilder();
+    
+    for (String word : words) {
+        if (word.trim().isEmpty()) {
+            capitalizedText.append(word);
+            continue;
+        }
+        capitalizedText.append(Character.toUpperCase(word.charAt(0)))
+                .append(word.substring(1));
+    }
+    
+    return capitalizedText.toString();
+}
+
+// Usage:
+System.out.println(capitalizeWords("hello  world")); // "Hello  World"
+```

snippets/java/string-manipulation/check-anagram.md

@@ -0,0 +1,28 @@
+---
+title: Check Anagram
+description: Checks if two strings are anagrams, meaning they contain the same characters ignoring order, spaces and case sensitivity
+author: Mcbencrafter
+tags: string,anagram,compare,arrays
+---
+
+```java
+import java.util.Arrays;
+
+public static boolean isAnagram(String text1, String text2) {
+    String text1Normalized = text1.replaceAll("\\s+", "");
+    String text2Normalized = text2.replaceAll("\\s+", "");
+
+    if (text1Normalized.length() != text2Normalized.length())
+        return false;
+        
+    char[] text1Array = text1Normalized.toCharArray();
+    char[] text2Array = text2Normalized.toCharArray();
+    Arrays.sort(text1Array);
+    Arrays.sort(text2Array);
+    return Arrays.equals(text1Array, text2Array);
+}
+
+// Usage:
+System.out.println(isAnagram("listen", "silent")); // true
+System.out.println(isAnagram("hello", "world"));   // false
+```

snippets/java/string-manipulation/check-palindrome.md

@@ -0,0 +1,20 @@
+---
+title: Check Palindrome
+description: Checks if a string reads the same backward as forward, ignoring whitespaces and case sensitivity
+author: Mcbencrafter
+tags: string,palindrome,compare,reverse
+---
+
+```java
+public static boolean isPalindrome(String text) {
+    String cleanText = text.toLowerCase().replaceAll("\\s+", "");
+        
+    return new StringBuilder(cleanText)
+            .reverse()
+            .toString()
+            .equals(cleanText);
+}
+
+// Usage:
+System.out.println(isPalindrome("A man a plan a canal Panama")); // true
+```

snippets/java/string-manipulation/count-character-frequency.md

@@ -0,0 +1,27 @@
+---
+title: Count Character Frequency
+description: Counts the frequency of each character in a string
+author: Mcbencrafter
+tags: string,character,frequency,character-frequency
+---
+
+```java
+public static Map<Character, Integer> characterFrequency(String text, boolean countSpaces, boolean caseSensitive) {
+    Map<Character, Integer> frequencyMap = new HashMap<>();
+
+    for (char character : text.toCharArray()) {
+        if (character == ' ' && !countSpaces)
+            continue;
+
+        if (!caseSensitive)
+            character = Character.toLowerCase(character);
+
+        frequencyMap.put(character, frequencyMap.getOrDefault(character, 0) + 1);
+    }
+
+    return frequencyMap;
+}
+
+// Usage:
+System.out.println(characterFrequency("hello world", false, false)); // {r=1, d=1, e=1, w=1, h=1, l=3, o=2}
+```

snippets/java/string-manipulation/count-character-occurrences.md

@@ -0,0 +1,26 @@
+---
+title: Count Character Occurrences
+description: Counts the occurrences of the specified characters in a given string
+author: Mcbencrafter
+tags: string,characters,counter,occurence
+---
+
+```java
+import java.util.List;
+
+public static int countCharacterOccurrences(String text, List<Character> characters) {
+    int count = 0;
+    
+    for (char character : text.toCharArray()) {
+        if (characters.indexOf(character) == -1)
+            continue;
+                
+        count++;
+    }
+    
+    return count;
+}
+
+// Usage:
+System.out.println(countCharacterOccurrences("hello world", List.of('l', 'o'))); // 5
+```

snippets/java/string-manipulation/count-words.md

@@ -0,0 +1,15 @@
+---
+title: Count Words
+description: Counts the number of words in a string
+author: Mcbencrafter
+tags: string,word,count
+---
+
+```java
+public static int countWords(String text) {
+    return text.split("\\s+").length;
+}
+
+// Usage:
+System.out.println(countWords("hello world")); // 2
+```

snippets/java/string-manipulation/extract-text-between-delimiters.md

@@ -0,0 +1,21 @@
+---
+title: Extract Text Between Delimiters
+description: Extracts a text between two given delimiters from a string
+author: Mcbencrafter
+tags: string,delimiters,start,end
+---
+
+```java
+public static String extractBetweenDelimiters(String text, String start, String end) {
+    int startIndex = text.indexOf(start);
+    int endIndex = text.indexOf(end, startIndex + start.length());
+    
+    if (startIndex == -1 || endIndex == -1)
+        return "";
+    
+    return text.substring(startIndex + start.length(), endIndex);
+}
+
+// Usage:
+System.out.println(extractBetweenDelimiters("hello, world!", ",", "!")); // " world"
+```

snippets/java/string-manipulation/find-longest-word.md

@@ -0,0 +1,25 @@
+---
+title: Find Longest Word
+description: Returns the longest word in a string
+author: Mcbencrafter
+tags: string,length,words
+---
+
+```java
+public static String findLongestWord(String text) {
+    String[] words = text.split("\\s+");
+    String longestWord = words[0];
+    
+    for (String word : words) {
+        if (word.length() <= longestWord.length())
+            continue;
+            
+        longestWord = word;
+    }
+
+    return longestWord;
+}
+
+// Usage:
+System.out.println(findLongestWord("hello world123")); // "world123"
+```