java-hashmap

hashmap

Port Java HashMap functionality to JavaScript. Quick and easy to pickup with the familiar syntax from Java.

Features

• Replicated HashMap syntax from Java
• Simple and easy to use
• Switch between HashMaps and Objects

Documentation

• Installation
• Creating a HashMap
• Interact with data
  • Add data
  • Remove data
  • Clear data
• Reading data
  • Getting values by keys
  • Getting all the data (in the form of Arrays)
  • Getting all the keys
  • Getting all the values
  • Getting the size of the HashMap
• Generate HashMap from Object/Array

Installation

Using npm:

$ npm install -g npm
$ npm install java-hashmap

In Node.js:

const HashMap = require("java-hashmap");

Creating a HashMap

The HashMap package returns a class, you can use this class to create a HashMap. For example, here is one of character colors:

const HashMap = require("hashmap");
var characterColors = new HashMap();

Interact with data

There isn't much use to a HashMap if you can't even deal with the information in it, so let's look at that.

Add data

To add data to the HashMap, use the .put() method. It takes two parameters, the key and the value.

characterColors.put("Sonic", "blue");
characterColors.put("Mario", "red");
characterColors.put("Ryu", "white");

Remove data

To remove data from the HashMap, use the .remove() method. It takes one parameter, the key.

characterColors.remove("Sonic");
characterColors.remove("Mario");
characterColors.remove("Ryu");

Clear data

To clear all the data from the HashMap, use the .clear() method.

characterColors.clear();

Reading data

The ability to modify data is no good if you can't even read it. So, there are a lot of methods with HashMaps for reading data.

Getting values by keys

To get a value by it's associated key, use the .get() method. It takes one parameter, the key.

characterColors.get("Sonic");
characterColors.get("Mario");
characterColors.get("Ryu");

Getting all the data (in the form of Arrays)

To get all the data in the form of two Arrays, use the .get() method without supplying any parameters.

characterColors.get();

Getting all the keys

To get all the keys, use the .keySet() method.

characterColors.keySet();

Getting all the values

To get all the values, use the .values() method.

characterColors.values();

Getting the size of the HashMap

To get all the size of the HashMap, use the .size() method.

characterColors.size();

Generate HashMap from Object/Array

Sometimes it's useful to generate a HashMap from an Object or an Array, to do so use the .generate() method.

const characterColors = new HashMap();

//With one Object
characterColors.generate({
    Sonic: "blue",
    Mario: "red",
    Ryu: "white"
});
/*["Sonic", "Mario", "Ryu"]
["blue", "red", "white"]*/

//With two Arrays
characterColors.generate(
    ["Sonic", "Mario", "Ryu"],
    ["blue", "red", "white"]);
/*["Sonic", "Mario", "Ryu"]
["blue", "red", "white"]*/

//With one Array
characterColors.generate(["Sonic", "Mario", "Ryu"]);
/*[0, 1, 2], ["Sonic", "Mario", "Ryu"]*/