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Convert List To Array In Java

Answer : Either: Foo[] array = list.toArray(new Foo[0]); or: Foo[] array = new Foo[list.size()]; list.toArray(array); // fill the array Note that this works only for arrays of reference types. For arrays of primitive types, use the traditional way: List<Integer> list = ...; int[] array = new int[list.size()]; for(int i = 0; i < list.size(); i++) array[i] = list.get(i); Update: It is recommended now to use list.toArray(new Foo[0]); , not list.toArray(new Foo[list.size()]); . From JetBrains Intellij Idea inspection: There are two styles to convert a collection to an array: either using a pre-sized array (like c.toArray(new String[c.size()]) ) or using an empty array (like c.toArray(new String[0]) . In older Java versions using pre-sized array was recommended, as the reflection call which is necessary to create an array of proper size was quite slow. However since late updates of OpenJDK 6 this call was intrinsified, making the performance of the empty a...