What is String pool in Java? [duplicate]

by

This prints true (even though we don’t use equals method: correct way to compare strings)

    String s = "a" + "bc";
    String t = "ab" + "c";
    System.out.println(s == t);

When compiler optimizes your string literals, it sees that both s and t have same value and thus you need only one string object. It’s safe because String is immutable in Java.
As result, both s and t point to the same object and some little memory saved.

Name ‘string pool’ comes from the idea that all already defined string are stored in some ‘pool’ and before creating new String object compiler checks if such string is already defined.

More Related Contents:

  1. Why 2 return statements are mandatory in equals method
  2. Scanner vs. BufferedReader
  3. Including jars in classpath on commandline (javac or apt)
  4. Why does this go into an infinite loop?
  5. What is the significance of load factor in HashMap?
  6. Distinction between the capacity of an array list and the size of an array
  7. How can I fix “unsupported class file major version 60” in IntelliJ IDEA?
  8. Does java have a int.tryparse that doesn’t throw an exception for bad data? [duplicate]
  9. Hibernate : How override an attribute from mapped super class
  10. How to send data to COM PORT using JAVA? [duplicate]
  11. What are the advantages of Enhanced for loop and Iterator in Java?
  12. CMSPermGenSweepingEnabled vs CMSClassUnloadingEnabled
  13. @OneToMany and composite primary keys?
  14. clone(): ArrayList.clone() I thought does a shallow copy
  15. mapping Hibernate query results to custom class?
  16. In Stream reduce method, must the identity always be 0 for sum and 1 for multiplication?
  17. Unit testing with Spring Security
  18. What does ‘->’ (arrow) mean in gradle’s dependency graph?
  19. Load arrayList data into JTable
  20. what is the use of MemoryFile in android
  21. Parse String date in (yyyy-MM-dd) format
  22. Which concurrent Queue implementation should I use in Java?
  23. PreparedStatements and performance
  24. Running java with JAVA_OPTS env variable has no effect
  25. How to downgrade Java from 9 to 8 on a MACOS. Eclipse is not running with Java 9
  26. Convert String[] to comma separated string in java
  27. JpaRepository caches newly created object. How to refresh it?
  28. java timer task schedule
  29. HQL joined query to eager fetch a large number of relationships
  30. Clarifying terminology – What does “hydrating” a JPA or Hibernate entity mean when fetching the entity from the DB

Leave a Comment