feat(xml-map): add map of string type serialization/deserialization support (#102)

This commit adds the support for serialization and deserialization of map of string type properties in the core library. This utility class will be used to annotate and handle map of string type properties in SDK models, ensuring proper serialization and deserialization.

Author: sufyankhanrao

src/main/java/io/apimatic/core/utilities/MapAdapter.java

@@ -0,0 +1,68 @@
+package io.apimatic.core.utilities;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+
+import javax.xml.bind.annotation.XmlAnyElement;
+import javax.xml.bind.annotation.adapters.XmlAdapter;
+import javax.xml.parsers.DocumentBuilder;
+import javax.xml.parsers.DocumentBuilderFactory;
+
+import org.w3c.dom.Document;
+import org.w3c.dom.Element;
+
+/**
+ * This is a utility class for XML map marshalling and unmarshalling.
+ */
+public class MapAdapter extends XmlAdapter<MapAdapter.EntryList, Map<String, String>> {
+
+    /**
+     * Holds the element entries of the map.
+     */
+    public static class EntryList {
+        @XmlAnyElement
+        private List<Element> entries = new ArrayList<Element>();
+
+        /**
+         * Getter for the element entries.
+         * @return entries The list of elements.
+         */
+        public List<Element> getEntries() {
+            return entries;
+        }
+    }
+
+    @Override
+    public EntryList marshal(Map<String, String> map) throws Exception {
+        if (map == null) {
+            return null;
+        }
+
+        DocumentBuilder docBuilder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
+        Document document = docBuilder.newDocument();
+        EntryList adaptedMap = new EntryList();
+        for (Entry<String, String> entry : map.entrySet()) {
+            Element element = document.createElement("entry");
+            element.setAttribute("key", entry.getKey());
+            element.setTextContent(entry.getValue());
+            adaptedMap.entries.add(element);
+        }
+        return adaptedMap;
+    }
+
+    @Override
+    public Map<String, String> unmarshal(EntryList adaptedMap) throws Exception {
+        if (adaptedMap == null) {
+            return null;
+        }
+
+        HashMap<String, String> map = new HashMap<String, String>();
+        for (Element element : adaptedMap.entries) {
+            map.put(element.getAttribute("key"), element.getTextContent());
+        }
+        return map;
+    }
+}

src/test/java/apimatic/core/utilities/MapAdapterTest.java

@@ -0,0 +1,149 @@
+package apimatic.core.utilities;
+
+import org.junit.Test;
+import org.w3c.dom.Document;
+import org.w3c.dom.Element;
+import io.apimatic.core.utilities.MapAdapter;
+import javax.xml.parsers.DocumentBuilder;
+import javax.xml.parsers.DocumentBuilderFactory;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+import java.util.HashMap;
+import java.util.Map;
+
+public class MapAdapterTest {
+
+    private final MapAdapter mapAdapter = new MapAdapter();
+
+    @Test
+    public void marshalShouldReturnEntryListWhenGivenNonEmptyMap() throws Exception {
+        // Arrange
+        Map<String, String> inputMap = new HashMap<>();
+        inputMap.put("key1", "value1");
+        inputMap.put("key2", "value2");
+
+        // Act
+        MapAdapter.EntryList result = mapAdapter.marshal(inputMap);
+
+        // Assert
+        assertEquals(2, result.getEntries().size());
+        assertTrue(result.getEntries().stream()
+                .anyMatch(e -> e.getAttribute("key").equals("key1")
+                        && e.getTextContent().equals("value1")));
+        assertTrue(result.getEntries().stream()
+                .anyMatch(e -> e.getAttribute("key").equals("key2")
+                        && e.getTextContent().equals("value2")));
+    }
+
+    @Test
+    public void marshalShouldReturnEmptyEntryListWhenGivenEmptyMap() throws Exception {
+        // Arrange
+        Map<String, String> inputMap = new HashMap<>();
+
+        // Act
+        MapAdapter.EntryList result = mapAdapter.marshal(inputMap);
+
+        // Assert
+        assertNotNull(result);
+        assertTrue(result.getEntries().isEmpty());
+    }
+
+    @Test
+    public void unmarshalShouldReturnMapWhenGivenNonEmptyEntryList() throws Exception {
+        // Arrange
+        DocumentBuilder docBuilder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
+        Document document = docBuilder.newDocument();
+        Element entry1 = document.createElement("entry");
+        entry1.setAttribute("key", "key1");
+        entry1.setTextContent("value1");
+
+        Element entry2 = document.createElement("entry");
+        entry2.setAttribute("key", "key2");
+        entry2.setTextContent("value2");
+
+        MapAdapter.EntryList entryList = new MapAdapter.EntryList();
+        entryList.getEntries().add(entry1);
+        entryList.getEntries().add(entry2);
+
+        // Act
+        Map<String, String> result = mapAdapter.unmarshal(entryList);
+
+        // Assert
+        assertEquals(2, result.size());
+        assertEquals("value1", result.get("key1"));
+        assertEquals("value2", result.get("key2"));
+    }
+
+    @Test
+    public void unmarshalShouldReturnEmptyMapWhenGivenEmptyEntryList() throws Exception {
+        // Arrange
+        MapAdapter.EntryList entryList = new MapAdapter.EntryList();
+
+        // Act
+        Map<String, String> result = mapAdapter.unmarshal(entryList);
+
+        // Assert
+        assertNotNull(result);
+        assertTrue(result.isEmpty());
+    }
+
+    @Test
+    public void marshalShouldHandleNullValues() throws Exception {
+        // Arrange
+        Map<String, String> inputMap = new HashMap<>();
+        inputMap.put("key1", null);
+
+        // Act
+        MapAdapter.EntryList result = mapAdapter.marshal(inputMap);
+
+        // Assert
+        assertEquals(1, result.getEntries().size());
+        assertEquals("", result.getEntries().get(0).getTextContent());
+    }
+
+    @Test
+    public void marshalShouldHandleNullMap() throws Exception {
+        // Arrange
+        Map<String, String> inputMap = null;
+
+        // Act
+        MapAdapter.EntryList result = mapAdapter.marshal(inputMap);
+
+        // Assert
+        assertNull(result);
+    }
+
+    @Test
+    public void unmarshalShouldHandleNullEntry() throws Exception {
+        // Arrange
+        MapAdapter.EntryList entryList = null;
+
+        // Act
+        Map<String, String> result = mapAdapter.unmarshal(entryList);
+
+        // Assert
+        assertNull(result);
+    }
+
+    @Test
+    public void unmarshalShouldHandleEntriesWithEmptyTextContent() throws Exception {
+        // Arrange
+        DocumentBuilder docBuilder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
+        Document document = docBuilder.newDocument();
+        Element entry1 = document.createElement("entry");
+        entry1.setAttribute("key", "key1");
+        entry1.setTextContent("");
+
+        MapAdapter.EntryList entryList = new MapAdapter.EntryList();
+        entryList.getEntries().add(entry1);
+
+        // Act
+        Map<String, String> result = mapAdapter.unmarshal(entryList);
+
+        // Assert
+        assertEquals(1, result.size());
+        assertEquals("", result.get("key1"));
+    }
+}