Update chaincode to be compatible with doc.

E.g. Return key of the queried record

Signed-off-by: Stefan Obermeier <scray@stefan-obermeier.de>

chaincode/fabcar/java/src/main/java/org/hyperledger/fabric/samples/fabcar/CarQueryResult.java

@@ -0,0 +1,68 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package org.hyperledger.fabric.samples.fabcar;
+
+import java.util.Objects;
+
+import org.hyperledger.fabric.contract.annotation.DataType;
+import org.hyperledger.fabric.contract.annotation.Property;
+
+import com.owlike.genson.annotation.JsonProperty;
+
+/**
+ * CarQueryResult structure used for handling result of query
+ *
+ */
+@DataType()
+public final class CarQueryResult {
+	@Property()
+	private final String key;
+	
+	@Property()
+	private final Car record;
+	
+	public CarQueryResult(@JsonProperty("Key") final String key, @JsonProperty("Record") final Car record) {
+		this.key = key;
+		this.record = record;
+	}
+	
+    public String getKey() {
+		return key;
+	}
+
+	public Car getRecord() {
+		return record;
+	}
+
+	@Override
+    public boolean equals(final Object obj) {
+        if (this == obj) {
+            return true;
+        }
+
+        if ((obj == null) || (getClass() != obj.getClass())) {
+            return false;
+        }
+
+        CarQueryResult other = (CarQueryResult) obj;
+
+        Boolean recordsAreEquals = this.getRecord().equals(other.getRecord());
+        Boolean keysAreEquals = this.getKey().equals(other.getKey());
+        
+        return recordsAreEquals && keysAreEquals;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(this.getKey(), this.getRecord());
+    }
+    
+    @Override
+	public String toString() {
+		return "{\"Key\":\"" + key + "\"" +  "\"Record\":{\"" + record + "}\"}";
+	}
+	
+}
+

chaincode/fabcar/java/src/main/java/org/hyperledger/fabric/samples/fabcar/FabCar.java

@@ -140,21 +140,21 @@ public final class FabCar implements ContractInterface {
      * @return array of Cars found on the ledger
      */
     @Transaction()
-    public Car[] queryAllCars(final Context ctx) {
+    public CarQueryResult[] queryAllCars(final Context ctx) {
         ChaincodeStub stub = ctx.getStub();
 
         final String startKey = "CAR0";
         final String endKey = "CAR999";
-        List<Car> cars = new ArrayList<Car>();
+        List<CarQueryResult> queryResults = new ArrayList<CarQueryResult>();
         
         QueryResultsIterator<KeyValue> results = stub.getStateByRange(startKey, endKey);
         
         for (KeyValue result: results) {
-            Car car = genson.deserialize(result.getStringValue(), Car.class);
-            cars.add(car);
-        }
         	
-        Car[] response = cars.toArray(new Car[cars.size()]);
+            Car car = genson.deserialize(result.getStringValue(), Car.class);
+            queryResults.add(new CarQueryResult(result.getKey(), car));
+        }
+        CarQueryResult[] response = queryResults.toArray(new CarQueryResult[queryResults.size()]);
 
         return response;
     }

chaincode/fabcar/java/src/test/java/org/hyperledger/fabric/samples/fabcar/FabCarTest.java

@@ -213,14 +213,14 @@ public final class FabCarTest {
         when(ctx.getStub()).thenReturn(stub);
         when(stub.getStateByRange("CAR0", "CAR999")).thenReturn(new MockCarResultsIterator());
 
-        Car[] cars = contract.queryAllCars(ctx);
+        CarQueryResult[] cars = contract.queryAllCars(ctx);
 
-        final List<Car> expectedCars = new ArrayList<Car>();
+        final List<CarQueryResult> expectedCars = new ArrayList<CarQueryResult>();
-        expectedCars.add(new Car("Toyota", "Prius", "blue", "Tomoko"));
+        expectedCars.add(new CarQueryResult("CAR0", new Car("Toyota", "Prius", "blue", "Tomoko")));
-        expectedCars.add(new Car("Ford", "Mustang", "red", "Brad"));
+        expectedCars.add(new CarQueryResult("CAR1", new Car("Ford", "Mustang", "red", "Brad")));
-        expectedCars.add(new Car("Hyundai", "Tucson", "green", "Jin Soo"));
+        expectedCars.add(new CarQueryResult("CAR2", new Car("Hyundai", "Tucson", "green", "Jin Soo")));
-        expectedCars.add(new Car("Fiat", "Punto", "violet", "Pari"));
+        expectedCars.add(new CarQueryResult("CAR7", new Car("Fiat", "Punto", "violet", "Pari")));
-        expectedCars.add(new Car("Holden", "Barina", "brown", "Shotaro"));
+        expectedCars.add(new CarQueryResult("CAR9", new Car("Holden", "Barina", "brown", "Shotaro")));
 
         assertThat(cars).containsExactlyElementsOf(expectedCars);
     }
@@ -239,7 +239,7 @@ public final class FabCarTest {
 
             Car car = contract.changeCarOwner(ctx, "CAR0", "Dr Evil");
 
-            assertThat(car).isEqualTo(new Car("Toyota", "Prius", "blue", "Dr Evil"));
+            assertThat(car).isEqualTo(new CarQueryResult("CAR0", new Car("Toyota", "Prius", "blue", "Dr Evil")));
         }
 
         @Test