CODEWITHSUNDEEP
javastringsplithashmap
cb269
cb269

Reputation: 21

How to sort a string into a map and print the results

I have a string in the format nm=Alan&hei=72&hair=brown

I would like to split this information up, add a conversion to the first value and print the results in the format

nm Name Alan
hei Height 72
hair Hair Color brown

I've looked at various methods using the split function and hashmaps but have had no luck piecing it all together.

Any advice would be very useful to me.

Upvotes: 0

Views: 149

Answers (4)

AlexR
AlexR

Reputation: 115338

Map<String, String> aliases = new HashMap<String, String>();
aliases.put("nm", "Name");
aliases.put("hei", "Height");
aliases.put("hair", "Hair Color");

String[] params = str.split("&"); // gives you string array: nm=Alan, hei=72, hair=brown

for (String p : params) {
    String[] nv = p.split("=");
    String name = nv[0];
    String value = nv[1];
    System.out.println(nv[0] + " " + aliases.get(nv[0]) + " " + nv[1]);
}

I really do not understand what you problem was...

Upvotes: 3

Nico Huysamen
Nico Huysamen

Reputation: 10417

Map<String, String> propsMap = new HashMap<String, String>();
Map<String, String> propAlias = new HashMap<String, String>();

propAlias.put("nm", "Name");
propAlias.put("hei", "Height");
propAlias.put("hair", "Hair Color");

String[] props = input.split("&");

if (props != null && props.length > 0) {
    for (String prop : props) {
        String[] propVal = prop.split("=");

        if (propVal != null && propVal.length == 2) {
            propsMap.put(propVal[0], propVal[1]);
        }
    }
}

for (Map.Entry tuple : propsMap.getEntrySet()) {
    if (propAlias.containsKey(tuple.getKey())) {
        System.out.println(tuple.getKey() + " " + propAlias.get(tuple.getKey()) + " " + tuple.getValue());
    }
}

Upvotes: 0

Dhruv Gairola
Dhruv Gairola

Reputation: 9182

A HashMap consists of many key, value pairs. So when you use split, devise an appropriate regex (&). Once you have your string array, you can use one of the elements as the key (think about which element will make the best key). However, you may now be wondering- "how do I place the rest of elements as the values?". Perhaps you can create a new class which stores the rest of the elements and use objects of this class as values for the hashmap.

Then printing becomes easy- merely search for the value of the corresponding key. This value will be an object; use the appropriate method on this object to retrieve the elements and you should be able to print everything.

Also, remember to handle exceptions in your code. e.g. check for nulls, etc.

Another thing: your qn mentions the word "sort". I don't fully get what that means in this context...

Upvotes: 0

Grook
Grook

Reputation: 405

Try something like this:

static final String DELIMETER = "&"
Map<String,String> map = ...
map.put("nm","Name");
map.put("hei","Height");
map.put("hair","Hair color");

StringBuilder builder = new StringBuilder();
String input = "nm=Alan&hei=72&hair=brown"
String[] splitted = input.split(DELIMETER);
for(Stirng str : splitted){
     int index = str.indexOf("=");     
     String key = str.substring(0,index);
     builder.append(key);
     builder.append(map.get(key));
     builder.append(str.substring(index));
     builder.append("\n");
}

Upvotes: 0

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