Added scaffolding for reports with multiple timestamps

README.md

@@ -74,6 +74,7 @@ code that uses data from [OpenWeathermap.org](https://openweathermap.org).
        forecast data set
      - [*air_pollution*](https://openweathermap.org/api/air-pollution), the air
        quality and pollution data set
+       - Includes *air_pollution/forecast* and *air_pollution/history*
 6. The remaining `OpenWeatherConnector` methods provide typed values for the
    JSON fields in the data loaded by `retrieveData(String)`.
 
@@ -94,4 +95,7 @@ code that uses data from [OpenWeathermap.org](https://openweathermap.org).
   not needed for our intended use of `OpenWeatherConnector`. (Also,
   `RestConnection` does not (yet) support PUSH and PUT calls, which would be
   required for those APIs.)
-- I need to write some tests.
\ No newline at end of file
+- Three-hour rain (and three-hour snow) total defaults to the 1-hour rain (snow)
+  when a separate 3-hour value is not reported. Recent real-world data calls
+  into question the assumption that a 3-hour value will be reported when rain
+  has fallen for more than an hour (or even more than three hours)
\ No newline at end of file

pom.xml

@@ -18,8 +18,8 @@
                 <artifactId>maven-compiler-plugin</artifactId>
                 <version>3.8.1</version>
                 <configuration>
-                    <source>8</source>
-                    <target>8</target>
+                    <source>11</source>
+                    <target>11</target>
                 </configuration>
             </plugin>
             <plugin>
@@ -28,8 +28,8 @@
                 <version>3.3.1</version>
                 <configuration>
                     <show>public</show>
-                    <source>8</source>
-                    <target>8</target>
+                    <source>11</source>
+                    <target>11</target>
                 </configuration>
             </plugin>
         </plugins>

src/main/java/edu/unl/cse/soft160/json_connections/Main.java

@@ -16,11 +16,11 @@ public class Main {
             System.err.println("Caused by: " + ioException.getCause());
             System.err.println("\t" + ioException.getCause().getMessage());
         }
-        OpenWeatherConnector weather = new OpenWeatherConnector("weather", apiKey);
-//        OpenWeatherConnector weather = new OpenWeatherConnector("weather");
+//        OpenWeatherConnector weather = new OpenWeatherConnector("weather", apiKey);
+        OpenWeatherConnector weather = new OpenWeatherConnector("air_pollution/history", apiKey);
         String data = null;
         try {
-            data = weather.retrieveData("zip=68588");
+            data = weather.retrieveData("lat=40.8194698&lon=-96.7066454&start=1606223802&end=1606482999");
 //            data = weather.retrieveData("website-example.json");
         } catch (IOException ioException) {
             System.err.println("IO Exception: " + ioException.getClass());

src/main/java/edu/unl/cse/soft160/json_connections/connector/OpenWeatherConnector.java

@@ -13,6 +13,8 @@ import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Date;
 import java.util.List;
+import java.util.Set;
+import java.util.stream.Collectors;
 
 /**
  * Wrapper for {@link Connection}s to OpenWeather data sources. Provides methods to extract values from OpenWeather
@@ -50,56 +52,50 @@ public class OpenWeatherConnector {
     }
 
     /**
-     * Convenience enums corresponding to documented OpenWeathermap APIs.
+     * Supported data sets, a subset of the documented OpenWeathermap APIs.
      */
-    protected enum DataSet {
-        WEATHER, ONECALL, FORECAST, AIR_POLLUTION, DIRECT, REVERSE,
-        // STATIONS, TRIGGERS,      // PUT/POST calls
-        // MAP,                     // map certainly isn't JSON, but it also appears not to be a REST call
-    }
-
+    public static final Set<String> allowableDataSets = Set.of(
+            "weather",
+            "onecall",
+            "forecast",
+            "air_pollution", "air_pollution/forecast", "air_pollution/history",
+            "direct", "reverse"         // geocoding
+            // "stations", "triggers"   excluded because PUT/POST calls are not supported here
+            // "map"                    excluded because it isn't JSON and also appears not to be a REST call
+    );
+
+    public static final Date IMPOSSIBLE_DATE = new Date(Long.MIN_VALUE);
     public static final String PROTOCOL = "http";
     public static final String REST_AUTHORITY = "api.openweathermap.org";
-    protected static String REST_PATH;  // Should be able to declare this as final, but static analysis doesn't see that
 
     protected final Connection dataSource;
-    protected final DataSet dataSet;
+    protected String dataSet;
+    protected String REST_PATH;     // Should be able to declare this as final, but static analysis doesn't see that
 
     protected JSONObject data;
+    protected Date currentTimestamp;
 
     /**
-     * Constructor to be used when connecting to OpenWeather data stored in a local file.
+     * <p>Constructor to be used when connecting to OpenWeather data stored in a local file.</p>
+     *
+     * <p><i>Note</i>: in the case of Air Pollution Forecast and Air Pollution History, the data set is of the form
+     * "air_pollution/forecast" and "air_pollution/history".</p>
      *
      * @param fileDataSet directory containing the specified file; must correspond to one of the
      *                    <a href="https://openweathermap.org/api">OpenWeathermap.org APIs</a>
      * @throws IllegalArgumentException if {@code fileDataSet} does not correspond to an OpenWeathermap.org API
      */
     public OpenWeatherConnector(String fileDataSet) throws IllegalArgumentException {
-        data = null;
-        try {
-            dataSet = DataSet.valueOf(fileDataSet.toUpperCase());
-        } catch (IllegalArgumentException illegalArgumentException) {
-            throw new IllegalArgumentException(fileDataSet + " is not a valid data set.", illegalArgumentException);
-        }
-        switch (dataSet) {
-            case WEATHER:
-            case ONECALL:
-            case FORECAST:
-            case AIR_POLLUTION:
-                REST_PATH = "/data/2.5/";
-                break;
-            case DIRECT:
-            case REVERSE:
-                REST_PATH = "/geo/1.0/";
-                break;
-            default:
-                REST_PATH = "unknown";
-        }
+        initializeFields(fileDataSet);
         dataSource = new FileConnection(fileDataSet);
     }
 
     /**
-     * Constructor to be used when connecting to <a href="https://openweathermap.org">OpenWeathermap.org</a>'s REST API.
+     * <p>Constructor to be used when connecting to <a href="https://openweathermap.org">OpenWeathermap.org</a>s's
+     * REST API.</p>
+     *
+     * <p><i>Note</i>: in the case of Air Pollution Forecast and Air Pollution History, the data set is of the form
+     * "air_pollution/forecast" and "air_pollution/history".</p>
      *
      * @param restDataSet specific <a href="https://openweathermap.org/api">OpenWeathermap.org API</a> to be used
      * @param apiKey      token provided by <a href="https://openweathermap.org">OpenWeathermap.org</a>
@@ -107,27 +103,33 @@ public class OpenWeatherConnector {
      * @throws IllegalArgumentException if {@code fileDataSet} does not correspond to an OpenWeathermap.org API
      */
     public OpenWeatherConnector(String restDataSet, String apiKey) throws IllegalArgumentException {
-        data = null;
-        try {
-            dataSet = DataSet.valueOf(restDataSet.toUpperCase());
-        } catch (IllegalArgumentException illegalArgumentException) {
-            throw new IllegalArgumentException(restDataSet + " is not a valid data set.", illegalArgumentException);
+        initializeFields(restDataSet);
+        dataSource = new RestConnection(PROTOCOL, REST_AUTHORITY, REST_PATH + restDataSet, apiKey);
+    }
+
+    private void initializeFields(String intendedDataSet) {
+        if(!allowableDataSets.contains(intendedDataSet)) {
+            throw new IllegalArgumentException(intendedDataSet + " is not a valid data set.");
         }
+        dataSet = intendedDataSet;
         switch (dataSet) {
-            case WEATHER:
-            case ONECALL:
-            case FORECAST:
-            case AIR_POLLUTION:
+            case "weather":
+            case "onecall":
+            case "forecast":
+            case "air_pollution":
+            case "air_pollution/forecast":
+            case "air_pollution/history":
                 REST_PATH = "/data/2.5/";
                 break;
-            case DIRECT:
-            case REVERSE:
+            case "direct":
+            case "reverse":
                 REST_PATH = "/geo/1.0/";
                 break;
             default:
                 REST_PATH = "unknown";
         }
-        dataSource = new RestConnection(PROTOCOL, REST_AUTHORITY, REST_PATH + restDataSet, apiKey);
+        data = null;
+        currentTimestamp = null;
     }
 
     /**
@@ -147,7 +149,7 @@ public class OpenWeatherConnector {
             data = dataSource.get(requestedData);
         } catch (FileNotFoundException fileNotFoundException) {
             if (dataSource instanceof RestConnection) {
-                throw new IOException("Could not access \"" + dataSet.toString().toLowerCase()
+                throw new IOException("Could not access \"" + dataSet.toLowerCase()
                         + "\" dataset at " + REST_AUTHORITY + ".",
                         fileNotFoundException);
             } else {
@@ -166,20 +168,22 @@ public class OpenWeatherConnector {
             if (dataSource instanceof FileConnection) {
                 message = "Error while parsing file " + requestedData + ".";
             } else if (dataSource instanceof RestConnection) {
-                message = "Error while parsing the " + dataSet.toString().toLowerCase()
+                message = "Error while parsing the " + dataSet.toLowerCase()
                         + " response from " + REST_AUTHORITY + ".";
             } else {
                 message = "Error while parsing requested data.";
             }
             throw new IOException(message, parseException);
         }
+        long unixTime = extractLongValue("dt", extractLongValue("current", "dt", Long.MIN_VALUE));
+        currentTimestamp = unixTime == Long.MIN_VALUE ? IMPOSSIBLE_DATE : new Date(unixTime * 1000);
         return data.toJSONString();
     }
 
     private void checkForDataPresence() throws IllegalStateException {
         if (data == null) {
             throw new IllegalStateException("No data has been retrieved from the "
-                    + dataSet.toString().toLowerCase() + " dataset.");
+                    + dataSet.toLowerCase() + " dataset.");
         }
     }
 
@@ -258,7 +262,7 @@ public class OpenWeatherConnector {
     }
 
     /**
-     * Provides the date and time for the weather.
+     * Provides the date and time for the current weather, or {@link #IMPOSSIBLE_DATE} if no valid timestamp exists.
      *
      * @return timestamp for the weather observations
      * @throws IllegalStateException if no data has been retrieved using {@link #retrieveData(String)}
@@ -266,8 +270,28 @@ public class OpenWeatherConnector {
      * @see #getLongitude()
      */
     public Date getTimestamp() throws IllegalStateException {
-        long unixTime = extractLongValue("dt", Long.MIN_VALUE);
-        return new Date(unixTime * 1000);
+        checkForDataPresence();
+        return currentTimestamp;
+    }
+
+    public List<Date> getTimeStamps() throws IllegalStateException {
+        checkForDataPresence();
+        Set<String> possibleListNames = Set.of("list", "minutely", "hourly", "daily");
+        List<Date> timestamps = new ArrayList<>();
+        for (String possibleListName : possibleListNames) {
+            if (data.containsKey(possibleListName)) {
+                JSONArray entries = (JSONArray)data.get(possibleListName);
+                if (entries != null) {
+                    timestamps = new ArrayList<>(entries.size());
+                    for (Object entry : entries) {
+                        long unixTime = (Long)((JSONObject)entry).get("dt");
+                        timestamps.add(new Date(unixTime));
+                    }
+                }
+            }
+        }
+        timestamps.sort(null);
+        return List.copyOf(timestamps);
     }
 
     /**
@@ -282,16 +306,21 @@ public class OpenWeatherConnector {
     public List<WeatherCategory> getWeatherCategories() throws IllegalStateException {
         checkForDataPresence();
         JSONArray weather = (JSONArray)data.get("weather");
-        List<WeatherCategory> categories = new ArrayList<>(weather.size());
-        for (Object condition : weather) {
-            String category = ((JSONObject)condition).get("main").toString();
-            try {
-                categories.add(WeatherCategory.valueOf(category.toUpperCase()));
-            } catch (IllegalArgumentException ignored) {
-                categories.add(WeatherCategory.UNKNOWN_CATEGORY);
+        List<WeatherCategory> categories;
+        if (weather != null) {
+            categories = new ArrayList<>(weather.size());
+            for (Object condition : weather) {
+                String category = ((JSONObject)condition).get("main").toString();
+                try {
+                    categories.add(WeatherCategory.valueOf(category.toUpperCase()));
+                } catch (IllegalArgumentException ignored) {
+                    categories.add(WeatherCategory.UNKNOWN_CATEGORY);
+                }
             }
+        } else {
+            categories = new ArrayList<>(0);
         }
-        return Collections.unmodifiableList(categories);
+        return List.copyOf(categories);
     }
 
     /**
@@ -306,11 +335,16 @@ public class OpenWeatherConnector {
     public List<String> getWeatherDescriptions() throws IllegalStateException {
         checkForDataPresence();
         JSONArray weather = (JSONArray)data.get("weather");
-        List<String> categories = new ArrayList<>(weather.size());
-        for (Object condition : weather) {
-            categories.add(((JSONObject)condition).get("description").toString());
+        List<String> descriptions;
+        if (weather != null) {
+            descriptions = new ArrayList<>(weather.size());
+            for (Object condition : weather) {
+                descriptions.add(((JSONObject)condition).get("description").toString());
+            }
+        } else {
+            descriptions = new ArrayList<>(0);
         }
-        return Collections.unmodifiableList(categories);
+        return List.copyOf(descriptions);
     }
 
     /**

src/test/java/edu/unl/cse/soft160/json_connections/UnlOct24At0917Test.java

@@ -43,7 +43,7 @@ public class UnlOct24At0917Test {
 
     @Test
     public void testWeather() {
-        List<OpenWeatherConnector.WeatherCategory> expectedCategories = Arrays.asList(
+        List<OpenWeatherConnector.WeatherCategory> expectedCategories = List.of(
                 OpenWeatherConnector.WeatherCategory.MIST,
                 OpenWeatherConnector.WeatherCategory.RAIN,
                 OpenWeatherConnector.WeatherCategory.THUNDERSTORM