Multidimensional array in Java like PHP

Question

I want to create an multidimensional array in Java, like the PHP one shown below. I want to create an exact same array. Is it possible?

Array
(
    [0] => Array
        (
            [name] => sagar
            [company] => Visa
        )

    [1] => Array
        (
            [name] => shloka
            [company] => Doctor
        )

    [2] => Array
        (
            [name] => sanket
            [company] => zon
        )

    [3] => Array
        (
            [name] => kamlesh
            [company] => nsc
        )

    [4] => Array
        (
            [name] => siddhi
            [company] => KES
        )

    [5] => Array
        (
            [name] => sanket
            [company] => zon
        )

    [6] => Array
        (
            [name] => bunty
            [company] => India Bull
        )

    [7] => Array
        (
            [name] => siddhi
            [company] => KES
        )

)

bezmax · Accepted Answer · 2012-03-09 06:52:44Z

5

The "Way of the Java" would be to make a POJO class to store that info, like this:

class UserInfo {
    private String name;
    private String company;

    public UserInfo(String name, String company) {
        this.name = name;
        this.company = company;
    }

    public String getName() {
        return name;
    }

    public String getCompany() {
        return company;
    }
}

UserInfo[] users = {
    new UserInfo("sagar", "visa"),
    new UserInfo("shloka", "Doctor"),
    ....
};

However, if you want it exactly the same way you did in PHP, there you go:

public static Map<String,String> createUser(String name, String company) {
    final Map<String,String> result = new HashMap<String,String>();
    result.put("name",name);
    result.put("company",company);
    return result;
}

List<Map<String,String>> users = new ArrayList<Map<String,String>>();
users.add(createUser("sagar","visa"));
users.add(createUser("shloka","Doctor"));
....

Added:

For the sake of completeness of the answer, here's another way using instance initializers. It may look prettier that the other solutions in some cases, but basically it has one flaw: it uses unrequired permgen space. Not much of it, but it is still unrequired:

List<Map<String,String>> result = new ArrayList<Map<String,String>>() {{ 
    add(new HashMap<String,String>() {{
        put("name", "someName");
        put("company", "someCompany");
    }}); 
    add(new HashMap<String,String>() {{
        put("name", "someName1");
        put("company", "someCompany1");
    }}); 
}};

Basically this solution is overriding an ArrayList with a new class (that's why a permgen is used) which has an instance initializer with addition commands. Each addition also uses an overriden HashMap class with an instance initializer. This may be considered a "synthetic sugar" for Java.

edited Mar 9, 2012 at 6:52

answered Mar 8, 2012 at 20:26

bezmax

26.3k11 gold badges55 silver badges84 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Ted Hopp Over a year ago

+1 for the addition, although it's somewhat on the baroque side. (Maybe we should call it "syntactic saccharine", since it leaves a bitter taste. :)) Just to pick a nit, though: you're using an instance initializer, not a static initializer.

bezmax Over a year ago

@TedHopp Yes, you are right about that initializer, going to rename it.

Pablo Santa Cruz · Accepted Answer · 2012-03-08 20:20:21Z

4

In your case, you need an array of maps.

Something like:

List<Map<String, String>> list = new ArrayList<Map<String, String>>();
// 0
Map<String, String> tmp = new HashMap<String, String>();
tmp.put("name", "sagar");
tmp.put("company", "Visa");
list.add(tmp);
// 1
tmp = new HashMap<String, String>();
tmp.put("name", "shloka");
tmp.put("company", "Doctor");
list.add(tmp);
// so on, so forth...

answered Mar 8, 2012 at 20:20

Pablo Santa Cruz

182k33 gold badges250 silver badges300 bronze badges

Comments

Ted Hopp · Accepted Answer · 2012-03-08 20:21:34Z

1

Java does not have associative arrays; you can use a List of Maps instead.

List<Map<String, String>> myArray = new ArrayList<Map<String, String>>();
for (int i = 0; i < max; ++i) {
    Map<String, String> map = new HashMap<String, String>();
    map.put("name", names[i]);
    map.put("company", companies[i]);
    myArray.add(map);
}

Unfortunately, there's no nice syntactic sugar that allows you to declare such a data structure without writing some procedural code.

answered Mar 8, 2012 at 20:21

Ted Hopp

235k48 gold badges412 silver badges533 bronze badges

1 Comment

bezmax Over a year ago

Well, actually there is one kind of "synthetic sugar" in Java. But would create lots of unrequired permgen space (not that much actually, but still unrequired). I updated my answer in case you are curious.

smcg · Accepted Answer · 2012-03-08 20:21:59Z

0

Multi-dimensional arrays in Java are done as arrays of arrays.

int foo[][] = new int[8][8];

foo[0][0] = 3;

But yes, you want an array of Maps in your case.

answered Mar 8, 2012 at 20:21

smcg

3,2733 gold badges32 silver badges40 bronze badges

Collectives™ on Stack Overflow

Multidimensional array in Java like PHP

4 Answers 4

2 Comments

Comments

1 Comment

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

2 Comments

Comments

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Related