feat: Add read-only getters for Point.fields and Point.tags

This makes testing easier.

Author: g3n35i5

client/src/main/java/com/influxdb/client/write/Point.java

@@ -30,6 +30,7 @@
 import java.util.Map;
 import java.util.Set;
 import java.util.TreeMap;
+import java.util.Collections;
 import java.util.concurrent.TimeUnit;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
@@ -95,6 +96,24 @@ public static Point measurement(@Nonnull final String measurementName) {
         return new Point(measurementName);
     }
 
+    /**
+     * Returns a read-only reference to the tags.
+     * @return The point tags as read-only map.
+     */
+    @Nonnull
+    public Map<String, String> getTags() {
+        return Collections.unmodifiableMap(this.tags);
+    }
+
+    /**
+     * Returns a read-only reference to the fields.
+     * @return The point fields as read-only map.
+     */
+    @Nonnull
+    public Map<String, Object> getFields() {
+        return Collections.unmodifiableMap(this.fields);
+    }
+
     /**
      * Adds or replaces a tag value for this point.
      *

client/src/test/java/com/influxdb/client/write/PointTest.java

@@ -24,13 +24,17 @@
 import java.math.BigDecimal;
 import java.math.BigInteger;
 import java.time.Instant;
+import java.util.Collections;
 import java.util.HashMap;
+import java.util.Map;
 
 import com.influxdb.client.domain.WritePrecision;
 
 import org.assertj.core.api.Assertions;
 import org.junit.jupiter.api.Test;
 
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
 /**
  * @author Jakub Bednar (bednar@github) (11/10/2018 12:57)
  */
@@ -438,4 +442,21 @@ void addFields() {
 
         Assertions.assertThat(point.toLineProtocol()).isEqualTo("h2o,location=europe accepted=true,level=2i,power=2.56");
     }
+
+    @Test
+    void getFieldsGetTags() {
+        Point point = Point.measurement("h2 o")
+                .addTag("location", "europe")
+                .addField("level", 2);
+
+        Map<String, Object> fields = point.getFields();
+        Map<String, String> tags = point.getTags();
+
+        Assertions.assertThat(fields).isEqualTo(Map.of("level",2L));
+        Assertions.assertThat(tags).isEqualTo(Map.of("location","europe"));
+
+        // Assert that returned maps are immutable
+        assertThrows(UnsupportedOperationException.class, () -> fields.put("test", "value"));
+        assertThrows(UnsupportedOperationException.class, () -> tags.put("test", "value"));
+    }
 }