Merge pull request #4 from aerospike/nel/java-quick-start

Add Java Quickstart Example

.gitignore

@@ -1,4 +1,6 @@
 .venv
 
 .vscode/
-.DS_Store
+.DS_Store
+
+examples/*/target

examples/java-example/README.md

@@ -0,0 +1,26 @@
+## To run Java example
+
+#### Reqs: Java 11+
+
+```
+cd ags_java_example
+mvn clean install -q
+java -jar target/ags-java-example-1.0-jar-with-dependencies.jar
+```
+Example output:
+```
+Connected to Aerospike Graph Service; Adding Data...
+Adding some users, accounts and transactions.
+Data written successfully...
+
+QUERY 1: Transactions initiated by Alice:
+Transaction Amount: 200, Receiver Account ID: A2
+Transaction Amount: 722, Receiver Account ID: A1
+Transaction Amount: 282, Receiver Account ID: A5
+...
+...
+...
+Dropping Dataset. 
+Closing Connection...
+
+```

examples/java-example/pom.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>aerospike.com</groupId>
+    <artifactId>ags-java-example</artifactId>
+    <version>1.0</version>
+    <packaging>jar</packaging>
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <tinkerpop.version>3.7.2</tinkerpop.version>
+        <junit.version>4.13.1</junit.version>
+        <maven.compiler.source>11</maven.compiler.source>
+        <maven.compiler.target>11</maven.compiler.target>
+    </properties>
+    <dependencies>
+        <dependency>
+            <groupId>org.apache.tinkerpop</groupId>
+            <artifactId>gremlin-core</artifactId>
+            <version>${tinkerpop.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.tinkerpop</groupId>
+            <artifactId>gremlin-driver</artifactId>
+            <version>${tinkerpop.version}</version>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>11</source>
+                    <target>11</target>
+                </configuration>
+            </plugin>
+            <plugin>
+                <artifactId>maven-assembly-plugin</artifactId>
+                <executions>
+                    <execution>
+                        <phase>package</phase>
+                        <goals>
+                            <goal>single</goal>
+                        </goals>
+                    </execution>
+                </executions>
+                <configuration>
+                    <archive>
+                        <manifest>
+                            <addClasspath>true</addClasspath>
+                            <mainClass>aerospike.com.Main</mainClass>
+                        </manifest>
+                    </archive>
+                    <descriptorRefs>
+                        <descriptorRef>jar-with-dependencies</descriptorRef>
+                    </descriptorRefs>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+</project>

examples/java-example/src/main/java/aerospike/com/Main.java

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+package aerospike.com;
+import org.apache.tinkerpop.gremlin.structure.Vertex;
+import org.apache.tinkerpop.gremlin.structure.Edge;
+import org.apache.tinkerpop.gremlin.driver.Cluster;
+import org.apache.tinkerpop.gremlin.driver.remote.DriverRemoteConnection;
+import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversalSource;
+import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.__;
+
+import static org.apache.tinkerpop.gremlin.process.traversal.AnonymousTraversalSource.traversal;
+import org.apache.tinkerpop.gremlin.process.traversal.P;
+
+
+import java.time.LocalDate;
+import java.time.ZoneOffset;
+import java.time.format.DateTimeFormatter;
+import java.util.Random;
+
+
+public class Main {
+    // Define the host and port for connecting to the Aerospike Graph service
+    private static final String HOST = "localhost";
+    private static final int PORT = 8182;
+
+    // Build the Cluster object with connection details
+    private static final Cluster.Builder BUILDER = Cluster.build()
+            .addContactPoint(HOST)  // Add the contact point (host)
+            .port(PORT)             // Specify the port
+            .enableSsl(false);      // Disable SSL for this example (use true in production if needed)
+
+    public static void main(final String[] args) {
+        // Create a Cluster object for connecting to the graph database
+        final Cluster cluster = BUILDER.create();
+        // Initialize a GraphTraversalSource to interact with the graph
+        final GraphTraversalSource g = traversal().withRemote(DriverRemoteConnection.using(cluster));
+
+        System.out.println("Connected to Aerospike Graph Service; Adding Data...");
+
+        // Add users, accounts, and transactions
+        System.out.println("Adding some users, accounts and transactions");
+
+        // Add Users
+        final Vertex user1 = g.addV("User").property("userId", "U1").property("name", "Alice").property("age", 30).next();
+        final Vertex user2 = g.addV("User").property("userId", "U2").property("name", "Bob").property("age", 35).next();
+        final Vertex user3 = g.addV("User").property("userId", "U3").property("name", "Charlie").property("age", 25).next();
+        final Vertex user4 = g.addV("User").property("userId", "U4").property("name", "Diana").property("age", 28).next();
+        final Vertex user5 = g.addV("User").property("userId", "U5").property("name", "Eve").property("age", 32).next();
+
+        // Add Accounts
+        final Vertex account1 = g.addV("Account").property("accountId", "A1").property("balance", 5000).next();
+        final Vertex account2 = g.addV("Account").property("accountId", "A2").property("balance", 3000).next();
+        final Vertex account3 = g.addV("Account").property("accountId", "A3").property("balance", 4000).next();
+        final Vertex account4 = g.addV("Account").property("accountId", "A4").property("balance", 2000).next();
+        final Vertex account5 = g.addV("Account").property("accountId", "A5").property("balance", 6000).next();
+
+        // Link Users to Accounts
+        g.addE("owns").from(user1).to(account1).property("since", "2020").iterate();
+        g.addE("owns").from(user2).to(account2).property("since", "2021").iterate();
+        g.addE("owns").from(user3).to(account3).property("since", "2022").iterate();
+        g.addE("owns").from(user4).to(account4).property("since", "2023").iterate();
+        g.addE("owns").from(user5).to(account5).property("since", "2024").iterate();
+
+        // Add Transactions
+        g.addE("Transaction")
+                .from(account1).to(account2)
+                .property("transactionId", "T1")
+                .property("amount", 200)
+                .property("type", "debit")
+                .property("timestamp", convertTimestampToLong("2023-01-15"))
+                .iterate();
+
+        g.addE("Transaction")
+                .from(account2).to(account1)
+                .property("transactionId", "T2")
+                .property("amount", 150)
+                .property("type", "credit")
+                .property("timestamp", convertTimestampToLong("2023-01-16"))
+                .iterate();
+
+        // Add Transactions
+        final Random random = new Random();
+        for (final int i = 1; i <= 50; i++) {
+            final Vertex fromAccount = g.V().hasLabel("Account").sample(1).next();
+            final Vertex toAccount = g.V().hasLabel("Account").sample(1).next();
+            final int amount = random.nextInt(1000) + 1; // Random amount between 1 and 1000
+            final String transactionId = "T" + i;
+            final String type = random.nextBoolean() ? "debit" : "credit";
+            final String timestamp = String.format("2025-%02d-%02d", random.nextInt(11) + 1,random.nextInt(28) + 1); // Random date in January 2025
+
+            g.addE("Transaction")
+                    .from(fromAccount).to(toAccount)
+                    .property("transactionId", transactionId)
+                    .property("amount", amount)
+                    .property("type", type)
+                    .property("timestamp", convertTimestampToLong(timestamp))
+                    .iterate();
+        }
+        System.out.println("Data written successfully...");
+
+        // Query Example 1: Find all transactions initiated by a specific user
+        System.out.println("\nQUERY 1: Transactions initiated by Alice:");
+        g.V().has("User", "name", "Alice")
+                .out("owns")
+                .outE("Transaction")
+                .as("transaction")
+                .inV()
+                .values("accountId")
+                .as("receiver")
+                .select("transaction", "receiver")
+                .by("amount")
+                .by()
+                .forEachRemaining(result -> {
+                    System.out.println("Transaction Amount: " + result.get("transaction") + ", Receiver Account ID: " + result.get("receiver"));
+                });
+        // Query Example 2: Aggregate total transaction amounts for each user
+        System.out.println("\nQUERY 2: Total transaction amounts initiated by users:");
+        g.V().hasLabel("Account")
+                .group()
+                .by("accountId")
+                .by(
+                        __.outE("Transaction")
+                                .values("amount")
+                                .sum()
+                )
+                .forEachRemaining(System.out::println);
+        System.out.println("\nQUERY 3: Users who transferred greater than 100 to Alice:");
+        g.V().has("User", "name", "Alice")
+                .out("owns")
+                .inE("Transaction")
+                .has("amount", P.gte(100))
+                .outV()
+                .in("owns")
+                .valueMap("name")
+                .forEachRemaining(result -> {
+                    System.out.println("User: " + result);
+                });
+
+        // Query Example 4: List all properties of a specific user
+        System.out.println("\nQUERY 4: Properties of Bob:");
+        final Vertex bob = g.V().has("User", "name", "Bob").next();
+        bob.properties().forEachRemaining(property -> {
+            System.out.println(property.key() + " : " + property.value());
+        });
+
+
+        // Clean up
+        g.V().drop().iterate();
+        System.out.print("Dropping Dataset.");
+        try {
+            System.out.println("Closing Connection...");
+            cluster.close();
+        } catch (Exception e) {
+            System.err.println("Failed to Close Connection: " + e);
+        }
+    }
+
+    /**
+     * Converts a date string (e.g., "2023-01-15") into a long representing epoch milliseconds.
+     * @param date The date string in "yyyy-MM-dd" format.
+     * @return The epoch timestamp in milliseconds as a long.
+     */
+    private static long convertTimestampToLong(final String date) {
+        final DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd");
+        // Parse the date string to LocalDate
+        final LocalDate localDate = LocalDate.parse(date, formatter);
+        // Convert LocalDate to epoch milliseconds
+        return localDate.atStartOfDay(ZoneOffset.UTC).toInstant().toEpochMilli();
+    }
+}