Java Strings
Creating Strings
Java
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String str1 = "This is string 1!"; String str2 = new String("This is string 2"); String str3 = String.valueOf(1234);
Concatenation
Java
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String str1 = 1 + "one" + 1; // 1one1 String str2 = 2 + 2 + "two"; // 4two String str3 = "3" + 3 + "three"; // 33three String str4 = "4" + str1; // 41one1 String str5 = "5" + String.valueOf(5); // 55 String str6 = str2.concat(str3); // 4two33three
String Information
Java
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String str = "Welcome"; str.length(); // 7 str.indexOf("e"); // 1 str.indexOf("r"); // -1 str.charAt(2); // l str.substring(1,3); // el str.contains("c"); // true str.startsWith("W"); // true str.endsWith("e"); // true str.isBlank(); // false str.isEmpty(); // false str.lastIndexOf("e"); // 6
Comparison
Java
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String str1 = "Welcome"; String str2 = new String("Welcome"); String str3 = "welcome"; System.out.println(str1 == str2); // false System.out.println(str1.equals(str2)); // true System.out.println(str1.equals(str3)); //false System.out.println(str1.equalsIgnoreCase(str3)); //true System.out.println(str1.contains(str2)); // true System.out.println(str1.contains(str3)); // false System.out.println(str1.compareTo(str2)); // 0 System.out.println(str1.contentEquals(str2)); // true System.out.println(str1.contentEquals(str3)); // false
Manipulation
Java
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String str1 = "Welcome"; String str2 = " Welcome "; System.out.println(str1.toLowerCase()); // welcome System.out.println(str1.toUpperCase()); // WELCOME char[] char1 = str1.toCharArray(); // ['W','e','l','c','o','m','e'] System.out.println(char1); // Welcome String strArr[] = str1.split(""); // ["W","e","l","c","o","m","e"] System.out.println(String.join(",", strArr)); // W,e,l,c,o,m,e System.out.println(str2.trim()); // [Welcome] System.out.println(str2.stripLeading()); // [Welcome ] System.out.println(str2.stripTrailing()); // [ Welcome]