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Java String FAQs

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Java String FAQs

String is immutable sequence of chars. Common APIs: length, charAt, substring, equals, split.

Use equals() for content, not ==.

Heavy edits → StringBuilder.

Write one tiny example for String FAQs. Compile, print one result, and say the output out loud before you type.

Use String FAQs only when the problem needs it. Don’t force it into every program. Know one beginner trap.

Let's take this on the board with one tiny Main class — no extra files. Java String FAQs — shows length, substring, case change, and equalsIgnoreCase. Start from main, go line by line, and stop at each print. That output is the proof for String FAQs.

Exam tip

== vs equals() on String is a classic trap.

Example

// String methods
public class Main {
  public static void main(String[] args) {
    String s = "PrepPilot";
    System.out.println(s.length());
    System.out.println(s.substring(0, 4));
    System.out.println(s.toUpperCase());
    System.out.println("prep".equalsIgnoreCase("PREP"));
  }
}

Java String FAQs — shows length, substring, case change, and equalsIgnoreCase.

Short notes

DefString FAQs is a Java idea you should explain with one small example.
RuleKnow the keyword / API used for String FAQs. Type a tiny Main and print one result.
RememberFor String FAQs, say the output before you code.
TrapString FAQs — only memorising the heading. No example, no trap.
Immutable text
equals for content

// String methods public class Main { public static void main(String[] args) { String s = "PrepPilot"; System.out.println(s.length()); System.out.println(s.substring(0, 4)); System.out.println(s.toUpperCase()); System.out.println("prep".equalsIgnoreCase("PREP")); } }

Java String FAQs

Example

Short notes

Questions

Java String FAQs

Example

Short notes

Questions