JSON-java/Util.java

package org.json.junit;

import static org.junit.Assert.*;

import java.util.*;

import org.json.*;

/**
 * These are helpful utility methods that perform basic comparisons
 * between various objects. In most cases, the comparisons are not
 * order-dependent, or else the order is known.
 */
public class Util {

    /**
     * Compares two JSONArrays for equality.
     * The arrays need not be in the same order.
     * @param jsonArray created by the code to be tested
     * @param expectedJsonArray created specifically for comparing
     */
    public static void compareActualVsExpectedJsonArrays(JSONArray jsonArray,
            JSONArray expectedJsonArray) {
        assertTrue("jsonArray lengths should be equal",
                jsonArray.length() == expectedJsonArray.length());
        for (int i = 0; i < jsonArray.length(); ++i) {
            Object value = jsonArray.get(i);
            Object expectedValue = expectedJsonArray.get(i);
            compareActualVsExpectedObjects(value, expectedValue);
        }
    }

    /**
     * Compares two JSONObjects for equality. The objects need not be
     * in the same order 
     * @param jsonObject created by the code to be tested
     * @param expectedJsonObject created specifically for comparing
     */
    public static void compareActualVsExpectedJsonObjects(
            JSONObject jsonObject, JSONObject expectedJsonObject) {
        assertTrue("jsonObjects should have the same length",
                jsonObject.length() == expectedJsonObject.length());
        Iterator<String> keys = jsonObject.keys();
        while (keys.hasNext()) {
            String key = keys.next();
            Object value = jsonObject.get(key);
            Object expectedValue = expectedJsonObject.get(key);
            compareActualVsExpectedObjects(value, expectedValue);
        }
    }

    /**
     * Compare two objects for equality. Might be JSONArray, JSONObject,
     * or something else.
     * @param value created by the code to be tested
     * @param expectedValue created specifically for comparing
     * @param key key to the jsonObject entry to be compared
     */
    private static void compareActualVsExpectedObjects(Object value,
            Object expectedValue) {
        if (value instanceof JSONObject && expectedValue instanceof JSONObject) {
            JSONObject jsonObject = (JSONObject)value;
            JSONObject expectedJsonObject = (JSONObject)expectedValue;
            compareActualVsExpectedJsonObjects(
                    jsonObject, expectedJsonObject);
        } else if (value instanceof JSONArray && expectedValue instanceof JSONArray) {
            JSONArray jsonArray = (JSONArray)value;
            JSONArray expectedJsonArray = (JSONArray)expectedValue;
            compareActualVsExpectedJsonArrays(
                    jsonArray, expectedJsonArray);
        } else {
            /**
             * Certain helper classes (e.g. XML) may create Long instead of
             * Integer for small int values. As long as both are Numbers,
             * just compare the toString() values.
             * TODO: this may not work in the case where the underlying types
             * do not have the same precision.
             */
            if (!(value instanceof Number && expectedValue instanceof Number)) {
                assertTrue("object types should be equal for actual: "+
                    value.toString()+" ("+
                    value.getClass().toString()+") expected: "+
                    expectedValue.toString()+" ("+
                    expectedValue.getClass().toString()+")",
                    value.getClass().toString().equals(
                            expectedValue.getClass().toString()));
            }
            /**
             * When in doubt, compare by string
             * TODO: should not this be an else to the previous condition?
             */
            assertTrue("string values should be equal for actual: "+
                value.toString()+" expected: "+expectedValue.toString(),
                value.toString().equals(expectedValue.toString()));
        }
    }
}