[IO-537] BOMInputStream shouldn't sort array of BOMs in-place.

Author: garydgregory

src/changes/changes.xml

@@ -83,6 +83,9 @@ The <action> type attribute can be add,update,fix,remove.
       <action issue="IO-503" dev="ggregory" type="fix">
         Update platform requirement to Java 7.
       </action>
+      <action issue="IO-537" dev="ggregory" type="fix" due-to="Borys Zibrov">
+        BOMInputStream shouldn't sort array of BOMs in-place.
+      </action>
       <action issue="IO-506" dev="ggregory" type="update" due-to="Christian Schulte">
         Deprecate methods FileSystemUtils.freeSpaceKb().
       </action>

src/main/java/org/apache/commons/io/input/BOMInputStream.java

@@ -21,6 +21,7 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.Comparator;
 import java.util.List;
 
@@ -168,9 +169,10 @@ public BOMInputStream(final InputStream delegate, final boolean include, final B
             throw new IllegalArgumentException("No BOMs specified");
         }
         this.include = include;
+        List<ByteOrderMark> list = Arrays.asList(boms);
         // Sort the BOMs to match the longest BOM first because some BOMs have the same starting two bytes.
-        Arrays.sort(boms, ByteOrderMarkLengthComparator);
-        this.boms = Arrays.asList(boms);
+        Collections.sort(list, ByteOrderMarkLengthComparator);
+        this.boms = list;
 
     }