A Java collection of value pairs? (tuples?)

by

AbstractMap.SimpleEntry

Easy you are looking for this:

java.util.List<java.util.Map.Entry<String,Integer>> pairList= new java.util.ArrayList<>();

How can you fill it?

java.util.Map.Entry<String,Integer> pair1=new java.util.AbstractMap.SimpleEntry<>("Not Unique key1",1);
java.util.Map.Entry<String,Integer> pair2=new java.util.AbstractMap.SimpleEntry<>("Not Unique key2",2);
pairList.add(pair1);
pairList.add(pair2);

This simplifies to:

Entry<String,Integer> pair1=new SimpleEntry<>("Not Unique key1",1);
Entry<String,Integer> pair2=new SimpleEntry<>("Not Unique key2",2);
pairList.add(pair1);
pairList.add(pair2);

And, with the help of a createEntry method, can further reduce the verbosity to:

pairList.add(createEntry("Not Unique key1", 1));
pairList.add(createEntry("Not Unique key2", 2));

Since ArrayList isn’t final, it can be subclassed to expose an of method (and the aforementioned createEntry method), resulting in the syntactically terse:

TupleList<java.util.Map.Entry<String,Integer>> pair = new TupleList<>();
pair.of("Not Unique key1", 1);
pair.of("Not Unique key2", 2);

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