Create a read only map in Java
Description
The following code shows how to create a read only map.
Example
// w ww . j a v a 2s .c o m
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
public class Main {
public static void main(String[] argv) throws Exception {
Map map = new HashMap();
map = Collections.unmodifiableMap(map);
try {
map.put("key","new value");
} catch (UnsupportedOperationException e) {
System.out.println(e.getMessage());
}
}
}
The code above generates the following result.