Allow use of map for qualifiers in constructor

The `PackageURL` constructor should not require the use of `TreeMap`
and can just convert the map to a `TreeMap` if it isn't already.

Author: dwalluck

src/main/java/com/github/packageurl/PackageURL.java

@@ -94,7 +94,6 @@ public PackageURL(final String type, final String name) throws MalformedPackageU
     public PackageURL(final String type, final String namespace, final String name, final String version,
                       final TreeMap<String, String> qualifiers, final String subpath)
             throws MalformedPackageURLException {
-
         this.scheme = validateScheme("pkg");
         this.type = validateType(type);
         this.namespace = validateNamespace(namespace);
@@ -105,6 +104,24 @@ public PackageURL(final String type, final String namespace, final String name,
         verifyTypeConstraints(this.type, this.namespace, this.name);
     }
 
+    /**
+     * Constructs a new PackageURL object.
+     *
+     * @param type       the type of package (i.e. maven, npm, gem, etc)
+     * @param namespace  the name prefix (i.e. group, owner, organization)
+     * @param name       the name of the package
+     * @param version    the version of the package
+     * @param qualifiers an array of key/value pair qualifiers
+     * @param subpath    the subpath string
+     * @throws MalformedPackageURLException if parsing fails
+     * @since 1.0.0
+     */
+    public PackageURL(final String type, final String namespace, final String name, final String version,
+                      final Map<String, String> qualifiers, final String subpath)
+            throws MalformedPackageURLException {
+        this(type, namespace, name, version, (qualifiers == null) ? null : ((qualifiers instanceof TreeMap) ? (TreeMap<String, String>) qualifiers : new TreeMap<>(qualifiers)), subpath);
+    }
+
     /**
      * The PackageURL scheme constant
      */

src/test/java/com/github/packageurl/PackageURLTest.java

@@ -23,6 +23,8 @@
 
 import java.io.IOException;
 import java.io.InputStream;
+import java.util.HashMap;
+import java.util.Map;
 import java.util.TreeMap;
 
 import org.apache.commons.io.IOUtils;
@@ -128,14 +130,18 @@ public void testConstructorParameters() throws MalformedPackageURLException {
             final String subpath = testDefinition.optString("subpath", null);
 
             TreeMap<String, String> map = null;
+            Map<String, String> hashMap = null;
             if (qualifiers != null) {
                 map = qualifiers.toMap().entrySet().stream().collect(
                         TreeMap<String, String>::new,
                         (qmap, entry) -> qmap.put(entry.getKey(), (String) entry.getValue()),
                         TreeMap<String, String>::putAll
                 );
+                hashMap = new HashMap<>(map);
             }
 
+
+
             if (invalid) {
                 try {
                     PackageURL purl = new PackageURL(type, namespace, name, version, map, subpath);
@@ -163,6 +169,8 @@ public void testConstructorParameters() throws MalformedPackageURLException {
                     Assert.assertTrue(purl.getQualifiers().containsKey(key));
                     Assert.assertEquals(value, purl.getQualifiers().get(key));
                 });
+                PackageURL purl2 = new PackageURL(type, namespace, name, version, hashMap, subpath);
+                Assert.assertEquals(purl.getQualifiers(), purl2.getQualifiers());
             }
         }
     }