Pretty-print a Map in Java

java dictionary pretty-print
space_monkey picture space_monkey · Apr 12, 2012 · Viewed 160.3k times · Source

I am looking for a nice way to pretty-print a Map.

map.toString() gives me: {key1=value1, key2=value2, key3=value3}

I want more freedom in my map entry values and am looking for something more like this: key1="value1", key2="value2", key3="value3"

I wrote this little piece of code:

StringBuilder sb = new StringBuilder();
Iterator<Entry<String, String>> iter = map.entrySet().iterator();
while (iter.hasNext()) {
    Entry<String, String> entry = iter.next();
    sb.append(entry.getKey());
    sb.append('=').append('"');
    sb.append(entry.getValue());
    sb.append('"');
    if (iter.hasNext()) {
        sb.append(',').append(' ');
    }
}
return sb.toString();

But I am sure there is a more elegant and concise way to do this.

Answer

Arkadiusz Cieśliński picture Arkadiusz Cieśliński · Oct 28, 2013 
Arrays.toString(map.entrySet().toArray())

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