'find value in ArrayList<HashMap> and get the index

I have a ArrayList<HashMap<String, String>> and it looks something like this 

 [{code=123, name=tester, model=car1},{code=456, name=tester, model=car2},{code=789, name=tester, model=car3}]

And what I want to do is search through it to find if any model number equals car2 and get the index of the object (in this case 1) so i can print out the name. Whats the best way to do this?

javaandroid


Solution 1:[1]

Scan each element in your list and break when you've found your element.

int i;
for(i = 0; i < haystackList.size(); i++){
  if(haystackList.get(i).get("model").equals(needle)){
    // Break
  }
}

if(i == haystackList.size()){
// Failure
} else {
// Success
}

Solution 2:[2]

Not exactly an efficient solution, as it can end up going through the entire ArrayList twice, but it'll get the job done.

int index;
for( HashMap m : mapList )
{
    if( m.get( "model" ).equals( "car2" ) )
    {
        index = arrayList.indexOf( m );
        break;
    }
}

Solution 3:[3]

Loop through the ArrayList and check each HashMap:

for (HashMap map : arraylist) {
    if ("car2".equals(map.get("model"))) {
        System.out.println("index: " + arraylist.indexOf(map));
        System.out.println("name: " + map.get("name"));
        break;
    }
}

The break was included under the assumption that only one model will be car2.

Sources

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Source: Stack Overflow

Solution Source
Solution 1 Dan S
Solution 2 gla3dr
Solution 3

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