Write code to merge two List
//package com.book2s; import java.util.ArrayList; import java.util.Collections; import java.util.List; public class Main { public static void main(String[] argv) { List aList = java.util.Arrays.asList("asdf", "book2s.com"); List bList = java.util.Arrays.asList("asdf", "book2s.com"); System.out.println(merge(aList, bList)); }//from w w w . java2 s .co m public static <T> List<T> merge(final List<T> aList, final List<T> bList) { if (aList == null && bList == null) { return Collections.emptyList(); } if (aList != null && bList == null) { return Collections.unmodifiableList(aList); } if (aList == null && bList != null) { return Collections.unmodifiableList(bList); } ArrayList<T> list = new ArrayList<T>(); list.addAll(aList); for (T t : bList) { if (!list.contains(t)) { list.add(t); } } return list; } public static <T> void add(final List<T> toList, final List<T> fromList) { if (toList == null || fromList == null) { return; } for (T t : fromList) { if (!toList.contains(t)) { toList.add(t); } } } }