Using JSON to return a Java Map

Question

What's the best way to return a Java Map using the JSON format? My specific need is a key -> value association between a date and a number.

My concern is this: My structure basically contains N elements of the same type (a mapping between a date and a number), and I want to be able to quickly iterate through them in Javascript.

In XML, I would have:

<relation date='mydate' number='mynumber'/>
<relation date='mydate' number='mynumber'/>
...
<relation date='mydate' number='mynumber'/>

and I would use jQuery like this:

$(xml).find("relation").each(function() {
    $(this).attr("date"); // the date
    $(this).attr("number"); // the number
})

It's my first experience with JSON and I would like to know if I can do something similar.

coobird · Accepted Answer · 2009-05-25 12:33:50Z

8

Although I haven't tried it myself, the JSONObject of the Java implementation of JSON from json.org has a JSONObject(Map) constructor.

Once a JSON object is created from the Map, then a JSON string can be obtained by calling the toString method.

answered May 25, 2009 at 12:33

coobird

161k35 gold badges216 silver badges228 bronze badges

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

1 Comment

Jonik Over a year ago

Yeah, that works (I have tried it too - although mainly with String -> String Maps)

José Leal · Accepted Answer · 2009-05-25 12:31:28Z

0

String myJson = "{ ";
for (String key : myMap.keySet())
    myJson += key + " : " + "'" + myMap.get(key) + "',";
myJson += " } ";

I leave the last comma because it wont give us many problems. The javascript just ignores it.

Well, this respond your question but I guess that won't help much. Try posting a more specific one.

answered May 25, 2009 at 12:31

José Leal

8,1699 gold badges40 silver badges54 bronze badges

2 Comments

Jonik Over a year ago

Hmm... constructing the JSON string yourself when good libraries exist (see stackoverflow.com/questions/906530/…) isn't necessarily the best way, IMHO.

Jonik Over a year ago

More importantly, this fails to produce correct JSON in some cases, e.g. when the strings contain ' characters. (And this would not be fixed by quoting also the key, which you don't do now.)

Collectives™ on Stack Overflow

Using JSON to return a Java Map

2 Answers 2

1 Comment

2 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

2 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related