Merge pull request #857 from XIAYM-gh/master

Implemented custom duplicate key handling (#840)

src/main/java/org/json/JSONObject.java

@@ -15,17 +15,8 @@
 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.regex.Pattern;
 
 /**
@@ -205,6 +196,21 @@ public JSONObject(JSONObject jo, String ... names) {
      *             duplicated key.
      */
     public JSONObject(JSONTokener x) throws JSONException {
+        this(x, new JSONParserConfiguration());
+    }
+
+    /**
+     * Construct a JSONObject from a JSONTokener with custom json parse configurations.
+     *
+     * @param x
+     *            A JSONTokener object containing the source string.
+     * @param jsonParserConfiguration
+     *            Variable to pass parser custom configuration for json parsing.
+     * @throws JSONException
+     *             If there is a syntax error in the source string or a
+     *             duplicated key.
+     */
+    public JSONObject(JSONTokener x, JSONParserConfiguration jsonParserConfiguration) throws JSONException {
         this();
         char c;
         String key;
@@ -234,13 +240,14 @@ public JSONObject(JSONTokener x) throws JSONException {
 
             if (key != null) {
                 // Check if key exists
-                if (this.opt(key) != null) {
-                    // key already exists
+                boolean keyExists = this.opt(key) != null;
+                if (keyExists && !jsonParserConfiguration.isOverwriteDuplicateKey()) {
                     throw x.syntaxError("Duplicate key \"" + key + "\"");
                 }
-                // Only add value if non-null
+
                 Object value = x.nextValue();
-                if (value!=null) {
+                // Only add value if non-null
+                if (value != null) {
                     this.put(key, value);
                 }
             }
@@ -296,7 +303,6 @@ public JSONObject(Map<?, ?> m, JSONParserConfiguration jsonParserConfiguration)
 
     /**
      * Construct a JSONObject from a map with recursion depth.
-     *
      */
     private JSONObject(Map<?, ?> m, int recursionDepth, JSONParserConfiguration jsonParserConfiguration) {
         if (recursionDepth > jsonParserConfiguration.getMaxNestingDepth()) {
@@ -427,7 +433,25 @@ public JSONObject(Object object, String ... names) {
      *                duplicated key.
      */
     public JSONObject(String source) throws JSONException {
-        this(new JSONTokener(source));
+        this(source, new JSONParserConfiguration());
+    }
+
+    /**
+     * Construct a JSONObject from a source JSON text string with custom json parse configurations.
+     * This is the most commonly used JSONObject constructor.
+     *
+     * @param source
+     *            A string beginning with <code>{</code>&nbsp;<small>(left
+     *            brace)</small> and ending with <code>}</code>
+     *            &nbsp;<small>(right brace)</small>.
+     * @param jsonParserConfiguration
+     *            Variable to pass parser custom configuration for json parsing.
+     * @exception JSONException
+     *                If there is a syntax error in the source string or a
+     *                duplicated key.
+     */
+    public JSONObject(String source, JSONParserConfiguration jsonParserConfiguration) throws JSONException {
+        this(new JSONTokener(source), jsonParserConfiguration);
     }
 
     /**

src/main/java/org/json/JSONParserConfiguration.java

@@ -4,23 +4,77 @@
  * Configuration object for the JSON parser. The configuration is immutable.
  */
 public class JSONParserConfiguration extends ParserConfiguration {
+    /**
+     * Used to indicate whether to overwrite duplicate key or not.
+     */
+    private boolean overwriteDuplicateKey;
 
-  /**
-   * Configuration with the default values.
-   */
-  public JSONParserConfiguration() {
-    super();
-  }
+    /**
+     * Configuration with the default values.
+     */
+    public JSONParserConfiguration() {
+        this(false);
+    }
 
-  @Override
-  protected JSONParserConfiguration clone() {
-    return new JSONParserConfiguration();
-  }
+    /**
+     * Configure the parser with argument overwriteDuplicateKey.
+     *
+     * @param overwriteDuplicateKey Indicate whether to overwrite duplicate key or not.<br>
+     *                              If not, the JSONParser will throw a {@link JSONException}
+     *                              when meeting duplicate keys.
+     */
+    public JSONParserConfiguration(boolean overwriteDuplicateKey) {
+        super();
+        this.overwriteDuplicateKey = overwriteDuplicateKey;
+    }
 
-  @SuppressWarnings("unchecked")
-  @Override
-  public JSONParserConfiguration withMaxNestingDepth(final int maxNestingDepth) {
-    return super.withMaxNestingDepth(maxNestingDepth);
-  }
+    @Override
+    protected JSONParserConfiguration clone() {
+        JSONParserConfiguration clone = new JSONParserConfiguration(overwriteDuplicateKey);
+        clone.maxNestingDepth = maxNestingDepth;
+        return clone;
+    }
 
+    /**
+     * Defines the maximum nesting depth that the parser will descend before throwing an exception
+     * when parsing a map into JSONObject or parsing a {@link java.util.Collection} instance into
+     * JSONArray. The default max nesting depth is 512, which means the parser will throw a JsonException
+     * if the maximum depth is reached.
+     *
+     * @param maxNestingDepth the maximum nesting depth allowed to the JSON parser
+     * @return The existing configuration will not be modified. A new configuration is returned.
+     */
+    @SuppressWarnings("unchecked")
+    @Override
+    public JSONParserConfiguration withMaxNestingDepth(final int maxNestingDepth) {
+        JSONParserConfiguration clone = this.clone();
+        clone.maxNestingDepth = maxNestingDepth;
+
+        return clone;
+    }
+
+    /**
+     * Controls the parser's behavior when meeting duplicate keys.
+     * If set to false, the parser will throw a JSONException when meeting a duplicate key.
+     * Or the duplicate key's value will be overwritten.
+     *
+     * @param overwriteDuplicateKey defines should the parser overwrite duplicate keys.
+     * @return The existing configuration will not be modified. A new configuration is returned.
+     */
+    public JSONParserConfiguration withOverwriteDuplicateKey(final boolean overwriteDuplicateKey) {
+        JSONParserConfiguration clone = this.clone();
+        clone.overwriteDuplicateKey = overwriteDuplicateKey;
+
+        return clone;
+    }
+
+    /**
+     * The parser's behavior when meeting duplicate keys, controls whether the parser should
+     * overwrite duplicate keys or not.
+     *
+     * @return The <code>overwriteDuplicateKey</code> configuration value.
+     */
+    public boolean isOverwriteDuplicateKey() {
+        return this.overwriteDuplicateKey;
+    }
 }

src/main/java/org/json/ParserConfiguration.java

@@ -20,12 +20,12 @@ public class ParserConfiguration {
 
     /**
      * Specifies if values should be kept as strings (<code>true</code>), or if
-     * they should try to be guessed into JSON values (numeric, boolean, string)
+     * they should try to be guessed into JSON values (numeric, boolean, string).
      */
     protected boolean keepStrings;
 
     /**
-     * The maximum nesting depth when parsing a document.
+     * The maximum nesting depth when parsing an object.
      */
     protected int maxNestingDepth;
 
@@ -59,14 +59,14 @@ protected ParserConfiguration clone() {
         // map should be cloned as well. If the values of the map are known to also
         // be immutable, then a shallow clone of the map is acceptable.
         return new ParserConfiguration(
-            this.keepStrings,
-            this.maxNestingDepth
+                this.keepStrings,
+                this.maxNestingDepth
         );
     }
 
     /**
      * When parsing the XML into JSONML, specifies if values should be kept as strings (<code>true</code>), or if
-     * they should try to be guessed into JSON values (numeric, boolean, string)
+     * they should try to be guessed into JSON values (numeric, boolean, string).
      *
      * @return The <code>keepStrings</code> configuration value.
      */
@@ -78,22 +78,21 @@ public boolean isKeepStrings() {
      * When parsing the XML into JSONML, specifies if values should be kept as strings (<code>true</code>), or if
      * they should try to be guessed into JSON values (numeric, boolean, string)
      *
-     * @param newVal
-     *      new value to use for the <code>keepStrings</code> configuration option.
-     * @param <T> the type of the configuration object
-     * 
+     * @param newVal new value to use for the <code>keepStrings</code> configuration option.
+     * @param <T>    the type of the configuration object
      * @return The existing configuration will not be modified. A new configuration is returned.
      */
     @SuppressWarnings("unchecked")
     public <T extends ParserConfiguration> T withKeepStrings(final boolean newVal) {
-        T newConfig = (T)this.clone();
+        T newConfig = (T) this.clone();
         newConfig.keepStrings = newVal;
         return newConfig;
     }
 
     /**
      * The maximum nesting depth that the parser will descend before throwing an exception
-     * when parsing the XML into JSONML.
+     * when parsing an object (e.g. Map, Collection) into JSON-related objects.
+     *
      * @return the maximum nesting depth set for this configuration
      */
     public int getMaxNestingDepth() {
@@ -102,18 +101,19 @@ public int getMaxNestingDepth() {
 
     /**
      * Defines the maximum nesting depth that the parser will descend before throwing an exception
-     * when parsing the XML into JSONML. The default max nesting depth is 512, which means the parser
-     * will throw a JsonException if the maximum depth is reached.
+     * when parsing an object (e.g. Map, Collection) into JSON-related objects.
+     * The default max nesting depth is 512, which means the parser will throw a JsonException if
+     * the maximum depth is reached.
      * Using any negative value as a parameter is equivalent to setting no limit to the nesting depth,
      * which means the parses will go as deep as the maximum call stack size allows.
+     *
      * @param maxNestingDepth the maximum nesting depth allowed to the XML parser
-     * @param <T> the type of the configuration object
-     * 
+     * @param <T>             the type of the configuration object
      * @return The existing configuration will not be modified. A new configuration is returned.
      */
     @SuppressWarnings("unchecked")
     public <T extends ParserConfiguration> T withMaxNestingDepth(int maxNestingDepth) {
-        T newConfig = (T)this.clone();
+        T newConfig = (T) this.clone();
 
         if (maxNestingDepth > UNDEFINED_MAXIMUM_NESTING_DEPTH) {
             newConfig.maxNestingDepth = maxNestingDepth;

src/test/java/org/json/junit/JSONParserConfigurationTest.java

@@ -0,0 +1,45 @@
+package org.json.junit;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+import org.json.JSONParserConfiguration;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+public class JSONParserConfigurationTest {
+    private static final String TEST_SOURCE = "{\"key\": \"value1\", \"key\": \"value2\"}";
+
+    @Test(expected = JSONException.class)
+    public void testThrowException() {
+        new JSONObject(TEST_SOURCE);
+    }
+
+    @Test
+    public void testOverwrite() {
+        JSONObject jsonObject = new JSONObject(TEST_SOURCE, new JSONParserConfiguration(true));
+
+        assertEquals("duplicate key should be overwritten", "value2", jsonObject.getString("key"));
+    }
+
+    @Test
+    public void verifyDuplicateKeyThenMaxDepth() {
+        JSONParserConfiguration jsonParserConfiguration = new JSONParserConfiguration()
+                .withOverwriteDuplicateKey(true)
+                .withMaxNestingDepth(42);
+
+        assertEquals(42, jsonParserConfiguration.getMaxNestingDepth());
+        assertTrue(jsonParserConfiguration.isOverwriteDuplicateKey());
+    }
+
+    @Test
+    public void verifyMaxDepthThenDuplicateKey() {
+        JSONParserConfiguration jsonParserConfiguration = new JSONParserConfiguration()
+                .withMaxNestingDepth(42)
+                .withOverwriteDuplicateKey(true);
+
+        assertTrue(jsonParserConfiguration.isOverwriteDuplicateKey());
+        assertEquals(42, jsonParserConfiguration.getMaxNestingDepth());
+    }
+}