ConcurrentHashMap and Hashtable in Java

ConcurrentHashMap uses multiple buckets to store data. This avoids read locks and greatly improves performance over a HashTable. Both are thread safe, but there are obvious performance wins with ConcurrentHashMap.

When you read from a ConcurrentHashMap using get(), there are no locks, contrary to the HashTable for which all operations are simply synchronized. HashTable was released in old versions of Java whereas ConcurrentHashMap is a java 5+ thing.

HashMap is the best thing to use in a single threaded application.

Related Posts:

  1. What are the differences between a HashMap and a Hashtable in Java?
  2. Hashtable, HashMap, HashSet , hash table concept in Java collection framework
  3. What is a hash function in java?
  4. Printing a java map Map – How?
  5. What is a hash function in java?
  6. Java associative-array
  7. Is a Python dictionary an example of a hash table?
  8. Exception in thread “main” java.lang.StackOverflowError
  9. Difference between HashSet and HashMap?
  10. Exception in thread “main” java.lang.StackOverflowError
  11. Iterate through a HashMap [duplicate]
  12. C# Java HashMap equivalent
  13. C# Java HashMap equivalent
  14. Iterate through a HashMap [duplicate]
  15. What is the significance of load factor in HashMap?
  16. How to update a value, given a key in a hashmap?
  17. Collision resolution in Java HashMap
  18. Difference between HashMap and Map in Java..?
  19. Java Hashmap: How to get key from value?
  20. Sorting HashMap by values
  21. How to sort Map values by key in Java?
  22. HashMap get/put complexity
  23. What is a hash map in programming and where can it be used
  24. What is the difference between the HashMap and Map objects in Java?
  25. “Cannot create generic array of ..” – how to create an Array of Map?
  26. Good Hash Function for Strings
  27. Map of maps – how to keep the inner maps as maps?
  28. toring and Retrieving ArrayList values from hashmap
  29. What does Java option -Xmx stand for? [duplicate]
  30. How do I convert a String to an int in Java?
  31. What does Java option -Xmx stand for? [duplicate]
  32. Is there an invisible character that is not regarded as whitespace?
  33. Problem with gif with transparent background
  34. Finding white rectangle in an image
  35. 1000 * 60 * 60 * 24 * 30 results in a negative number [duplicate]
  36. How to convert nanoseconds to seconds using the TimeUnit enum?
  37. Search for words with telephone numbers from 2-3-4 tree
  38. How to do associative array/hashing in JavaScript
  39. Using or ‘|’ in regex [duplicate]
  40. How to format strings in Java
  41. What is the difference between x86 and x64
  42. && (AND) and || (OR) in IF statements
  43. How to use the toString method in Java?
  44. What is a NullPointerException, and how do I fix it?
  45. What exactly is Apache Camel?
  46. Unable to find valid certification path to requested target – error even after cert imported
  47. Unable to find valid certification path to requested target – error even after cert imported
  48. What is the equivalent of the C++ Pair in Java?
  49. Java – Convert integer to string [duplicate]
  50. Getting random numbers in Java [duplicate]
  51. What is an instance variable in Java?
  52. javac is not recognized as an internal or external command, operable program or batch file [closed]
  53. javac is not recognized as an internal or external command, operable program or batch file [closed]
  54. Java: “error: cannot find symbol”
  55. How does the Java ‘for each’ loop work?
  56. Which is the difference between Long.valueOf(0) and 0L in Java?
  57. What is a StackOverflowError?
  58. Use of “instanceof” in Java [duplicate]
  59. What is the best way to use a HashMap in C++?
  60. How to use Collections.sort() in Java?
  61. What is the best way to use a HashMap in C++?
  62. How to uninstall Eclipse?
  63. Is GNU’s Java Compiler (GCJ) dead? [closed]
  64. How does System.out.print() work?
  65. How do I “decompile” Java class files? [closed]
  66. How do I determine whether an array contains a particular value in Java?
  67. How to initialize an array in Java?
  68. How does the Java ‘for each’ loop work?
  69. Java 8 Iterable.forEach() vs foreach loop
  70. Initialize part of an array in java
  71. How can I solve Exception in thread “main” java.lang.NullPointerException error [duplicate]
  72. How to split a string in Java
  73. What does “Could not find or load main class” mean?
  74. What does “Could not find or load main class” mean?
  75. Why am I getting a NoClassDefFoundError in Java?
  76. How to avoid “ConcurrentModificationException” while removing elements from `ArrayList` while iterating it? [duplicate]
  77. Eclipse/Maven error: “No compiler is provided in this environment”
  78. How do I compare strings in Java?
  79. Is Java “pass-by-reference” or “pass-by-value”?
  80. What is reflection and why is it useful?
  81. Implementing UML diagram to Java [closed]
  82. How to round a number to n decimal places in Java
  83. Using Pairs or 2-tuples in Java [duplicate]
  84. How do I create a file and write to it?
  85. Hash Map in Python
  86. Could not reserve enough space for object heap
  87. Difference between java.exe and javaw.exe
  88. When to use LinkedList over ArrayList in Java?
  89. Can’t start Eclipse – Java was started but returned exit code=13
  90. How to convert a char to a String?
  91. Can’t start Eclipse – Java was started but returned exit code=13
  92. super() in Java
  93. Difference between Arrays.asList(array) and new ArrayList(Arrays.asList(array))
  94. What is the proper way to handle a NumberFormatException when it is expected?
  95. What causes “Unable to access jarfile” error?
  96. What does “Could not find or load main class” mean?
  97. How do you create a dictionary in Java? [closed]
  98. Reading a plain text file in Java
  99. Error unable to access jarfile C:\Jar
  100. Where is JRE 11? [duplicate]

Leave a Comment

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)