4 files changed, 66 insertions(+), 10 deletions(-)

M pom.xml
M src/main/fbs/person.fbs
M src/main/java/com/example/flatbuffers/FlatbuffersApplication.java
R src/main/java/com/example/flatbuffers/{WorkingOnFlatBuffers.java => GeneratingAndWriting.java}

@@ 35,6 35,11 @@
             <groupId>ch.qos.logback</groupId>
             <artifactId>logback-classic</artifactId>
         </dependency>
+        <dependency>
+            <groupId>org.apache.commons</groupId>
+            <artifactId>commons-lang3</artifactId>
+            <version>3.9</version>
+        </dependency>
     </dependencies>
 
     <build>

@@ 1,5 1,9 @@
 namespace com.example.flatbuffers.model;
 
+table People {
+    people:[Person];
+}
+
 table Person {
     firstName:string;
     lastName:string;

@@ 1,8 1,17 @@
 package com.example.flatbuffers;
 
+import org.apache.commons.lang3.time.StopWatch;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 public class FlatbuffersApplication {
+    private static final Logger LOGGER = LoggerFactory.getLogger(FlatbuffersApplication.class);
 
     public static void main(String[] args) {
-        new WorkingOnFlatBuffers().test();
+        StopWatch stopWatch = StopWatch.createStarted();
+        int numberOfPeople = 1_047_031;
+        new GeneratingAndWriting().writingPeople(numberOfPeople);
+        stopWatch.stop();
+        LOGGER.info("Generating and writig took: {}", stopWatch);
     }
 }

@@ 1,29 1,59 @@
 package com.example.flatbuffers;
 
 import com.example.flatbuffers.model.Address;
+import com.example.flatbuffers.model.People;
 import com.example.flatbuffers.model.Person;
 import com.google.flatbuffers.FlatBufferBuilder;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.io.FileOutputStream;
+import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.util.concurrent.ThreadLocalRandom;
 
 import static com.example.flatbuffers.Util.pickRandom;
 
-public class WorkingOnFlatBuffers {
+public class GeneratingAndWriting {
 
-    private static final Logger LOGGER = LoggerFactory.getLogger(WorkingOnFlatBuffers.class);
+    private static final Logger LOGGER = LoggerFactory.getLogger(GeneratingAndWriting.class);
 
     private static final String[] FIRST_NAMES = new String[]{"John", "Jane", "Gerard", "Aubrey", "Amelia"};
     private static final String[] LAST_NAMES = new String[]{"Smith", "Parker", "Phillips", "Jones"};
     private static final String[] STREETS = new String[]{
             "Halloway", "Sunset Boulvard", "Wall Street", "Secret Passageway"};
     private static final String[] CITIES = new String[]{"Brussels", "Paris", "London", "Amsterdam"};
-    public static final String PERSON_LINE_TEMPLATE = " * {}";
-    public static final String ADDRESS_LINE_TEMPLATE = "   * {} {}";
+    private static final String PERSON_LINE_TEMPLATE = " * {}";
+    private static final String ADDRESS_LINE_TEMPLATE = "   * {} {}";
+
+    public void writingPeople(int numberOfPeople) {
+        // Writing out data to file
+        try (FileOutputStream fd = new FileOutputStream("people.flatbuffers")) {
+            fd.write(createRandomPeople(numberOfPeople));
+        } catch (IOException e) {
+            LOGGER.error("Failed to write FlatBuffer data");
+        }
+    }
+
+    private byte[] createRandomPeople(int numberOfPeople) {
+        FlatBufferBuilder builder = new FlatBufferBuilder();
+
+        int[] personOffsets = new int[numberOfPeople];
+        for (int i = 0; i < numberOfPeople; i++) {
+            personOffsets[i] = buildRandomPerson(builder);
+        }
+
+        int peopleVector = People.createPeopleVector(builder, personOffsets);
+
+        People.startPeople(builder);
+        People.addPeople(builder, peopleVector);
+        int peopleOffset = People.endPeople(builder);
+
+        builder.finish(peopleOffset);
+        return builder.sizedByteArray();
+    }
 
-    public void test() {
+    public void writingAndReadingAPerson() {
         // Writing data into buffer
         ByteBuffer data = createPerson();
 


@@ 49,7 79,18 @@ public class WorkingOnFlatBuffers {
      */
     private ByteBuffer createPerson() {
         FlatBufferBuilder builder = new FlatBufferBuilder();
+        int person = buildRandomPerson(builder);
+        builder.finish(person);
+        return builder.dataBuffer();
+    }
 
+    /**
+     * Random person created in the builder
+     *
+     * @param builder FlatBufferBuilder to construct person
+     * @return offset of created person
+     */
+    private int buildRandomPerson(FlatBufferBuilder builder) {
         int street = builder.createString(randomStreet());
         int city = builder.createString(randomCity());
         int address = Address.createAddress(builder, street, randomStreetNumber(), city, randomPostalCode());


@@ 61,10 102,7 @@ public class WorkingOnFlatBuffers {
         Person.addFirstName(builder, firstName);
         Person.addLastName(builder, lastName);
         Person.addAddress(builder, address);
-        int person = Person.endPerson(builder);
-
-        builder.finish(person);
-        return builder.dataBuffer();
+        return Person.endPerson(builder);
     }
 
     private String randomFirstName() {