streams - JSONObject and JSONArray implement iterable, add stream() m…

…ethod to each class
stleary · Sep 4, 2023 · 252bfbb · 252bfbb
1 parent c29d488
commit 252bfbb
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Showing 4 changed files with 115 additions and 11 deletions.
diff --git a/src/main/java/org/json/JSONArray.java b/src/main/java/org/json/JSONArray.java
@@ -15,6 +15,8 @@
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.stream.IntStream;
+import java.util.stream.Stream;
 
 
 /**
@@ -224,6 +226,10 @@ public JSONArray(int initialCapacity) throws JSONException {
     	this.myArrayList = new ArrayList<Object>(initialCapacity);
     }
 
+    public Stream<Object> stream() {
+        return IntStream.range(0, length()).mapToObj(this::get);
+    }
+
     @Override
     public Iterator<Object> iterator() {
         return this.myArrayList.iterator();

diff --git a/src/main/java/org/json/JSONObject.java b/src/main/java/org/json/JSONObject.java
@@ -15,18 +15,11 @@
 import java.lang.reflect.Modifier;
 import java.math.BigDecimal;
 import java.math.BigInteger;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.Enumeration;
-import java.util.HashMap;
-import java.util.IdentityHashMap;
-import java.util.Iterator;
-import java.util.Locale;
-import java.util.Map;
+import java.util.*;
 import java.util.Map.Entry;
-import java.util.ResourceBundle;
-import java.util.Set;
+import java.util.function.Consumer;
 import java.util.regex.Pattern;
+import java.util.stream.Stream;
 
 /**
  * A JSONObject is an unordered collection of name/value pairs. Its external
@@ -81,7 +74,22 @@
  * @author JSON.org
  * @version 2016-08-15
  */
-public class JSONObject {
+public class JSONObject implements Iterable<String> {
+    @Override
+    public Iterator<String> iterator() {
+        return null;
+    }
+
+    @Override
+    public void forEach(Consumer<? super String> action) {
+        Iterable.super.forEach(action);
+    }
+
+    @Override
+    public Spliterator<String> spliterator() {
+        return Iterable.super.spliterator();
+    }
+
     /**
      * JSONObject.NULL is equivalent to the value that JavaScript calls null,
      * whilst Java's null is equivalent to the value that JavaScript calls
@@ -461,6 +469,10 @@ protected JSONObject(int initialCapacity){
         this.map = new HashMap<String, Object>(initialCapacity);
     }
 
+    public Stream<String> stream() {
+        return keySet().stream();
+    }
+
     /**
      * Accumulate values under a key. It is similar to the put method except
      * that if there is already an object stored under the key then a JSONArray

diff --git a/src/test/java/org/json/junit/JSONArrayTest.java b/src/test/java/org/json/junit/JSONArrayTest.java
@@ -24,6 +24,8 @@
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.stream.Collectors;
+import java.util.stream.StreamSupport;
 
 import org.json.JSONArray;
 import org.json.JSONException;
@@ -66,6 +68,42 @@ public class JSONArrayTest {
                 "\"-1\""+
             "]";
 
+    /**
+     * Tests the stream() API
+     */
+    public void testStream() {
+        String data = "[\n" +
+                "    {\n" +
+                "      \"id\": 1,\n" +
+                "      \"name\": \"Alice\",\n" +
+                "      \"department\": \"HR\"\n" +
+                "    },\n" +
+                "    {\n" +
+                "      \"id\": 2,\n" +
+                "      \"name\": \"Bonnie\",\n" +
+                "      \"department\": \"Engineering\"\n" +
+                "    },\n" +
+                "    {\n" +
+                "      \"id\": 3,\n" +
+                "      \"name\": \"Carol\",\n" +
+                "      \"department\": \"Marketing\"\n" +
+                "    }\n" +
+                "  ]";
+        JSONArray jsonArray = new JSONArray(data);
+
+        // Get employees from the engineering dept
+        List<String> actualList = StreamSupport.stream(jsonArray.spliterator(), false)
+                .map(JSONObject.class::cast)
+                .filter(employee -> "Engineering".equals(employee.getString("department")))
+                .map(employee -> employee.getString("name"))
+                .collect(Collectors.toList());
+
+        List<String> expectedList = new ArrayList<>();
+        expectedList.add("Bonnie");
+        assertEquals(actualList, expectedList);
+    }
+
+
     /**
      * Tests that the similar method is working as expected.
      */

diff --git a/src/test/java/org/json/junit/JSONObjectTest.java b/src/test/java/org/json/junit/JSONObjectTest.java
@@ -24,6 +24,7 @@
 import java.util.*;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.regex.Pattern;
+import java.util.stream.Collectors;
 
 import org.json.CDL;
 import org.json.JSONArray;
@@ -72,6 +73,53 @@ public class JSONObjectTest {
      */
     static final Pattern NUMBER_PATTERN = Pattern.compile("-?(?:0|[1-9]\\d*)(?:\\.\\d+)?(?:[eE][+-]?\\d+)?");
 
+    /**
+     * Tests the stream api
+     */
+    @Test
+    public void testStream() {
+        String data = "{\n" +
+                "  \"employees\": [\n" +
+                "    {\n" +
+                "      \"id\": 1,\n" +
+                "      \"name\": \"Alice\",\n" +
+                "      \"department\": \"HR\"\n" +
+                "    },\n" +
+                "    {\n" +
+                "      \"id\": 2,\n" +
+                "      \"name\": \"Bonnie\",\n" +
+                "      \"department\": \"Engineering\"\n" +
+                "    },\n" +
+                "    {\n" +
+                "      \"id\": 3,\n" +
+                "      \"name\": \"Carol\",\n" +
+                "      \"department\": \"Marketing\"\n" +
+                "    }\n" +
+                "  ]\n" +
+                "}";
+
+        JSONObject jsonObject = new JSONObject(data);
+
+        // Get employees from the Engineering department
+        List<String> actualList = new ArrayList<>();
+
+        jsonObject.stream()
+                .filter(key -> key.startsWith("employees"))
+                .map(jsonObject::getJSONArray)
+                .flatMap(JSONArray::stream)
+                .map(JSONObject.class::cast)
+                .filter(employee -> "Engineering".equals(employee.getString("department")))
+                .map(employee -> employee.getString("name"))
+                .forEach(name -> actualList.add(name));
+
+        List<String> expectedList = new ArrayList<>();
+        expectedList.add("Bonnie");
+        assertEquals(expectedList, actualList);
+    }
+
+
+
+
     /**
      * Tests that the similar method is working as expected.
      */