var infers the type without losing it

var is still static typing - the compiler fixes the type at the declaration. It shines on long generic types and in for loops.

Code

var byCategory = new TreeMap<String, List<String>>();
byCategory.computeIfAbsent("java", k -> new ArrayList<>()).add("streams");
byCategory.computeIfAbsent("java", k -> new ArrayList<>()).add("records");

for (var entry : byCategory.entrySet()) {
    System.out.println(entry.getKey() + " -> " + entry.getValue());
}

var total = 0;
for (var i = 1; i <= 5; i++) total += i;
System.out.println("total = " + total + " (inferred int)");

Output

java -> [streams, records]
total = 15 (inferred int)

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Published 2026-07-30