Map to String in Java

java map tostring
Dan picture Dan · May 13, 2010 · Viewed 166.7k times · Source

When I do System.out.println(map) in Java, I get a nice output in stdout. How can I obtain this same string representation of a Map in a variable without meddling with standard output? Something like String mapAsString = Collections.toString(map)?

Answer

BalusC picture BalusC · May 13, 2010

Use Object#toString().

String string = map.toString();

That's after all also what System.out.println(object) does under the hoods. The format for maps is described in AbstractMap#toString().

Returns a string representation of this map. The string representation consists of a list of key-value mappings in the order returned by the map's entrySet view's iterator, enclosed in braces ("{}"). Adjacent mappings are separated by the characters ", " (comma and space). Each key-value mapping is rendered as the key followed by an equals sign ("=") followed by the associated value. Keys and values are converted to strings as by String.valueOf(Object).

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