Java uses JGraphT to serialize and deserialize graphs
In Java, the JGraphT library can be used to handle graph serialization and deserialization operations. JGraphT is an open source Java graph library that provides a rich set of graph algorithms and data structures that can help us create, manipulate, and analyze various types of graphs.
Before implementing the serialization and deserialization of graphs, it is first necessary to add the JGraphT library as a dependency of the project. Here are the Maven coordinates of JGraphT:
<dependency>
<groupId>org.jgrapht</groupId>
<artifactId>jgrapht-core</artifactId>
<version>1.5.0</version>
</dependency>
The above coordinates specify that the version of the jgrapht core library is 1.5.0.
Next, we will demonstrate how to use the JGraphT library to serialize and deserialize graphs. Here is a complete Java code example:
import org.jgrapht.Graph;
import org.jgrapht.graph.DefaultEdge;
import org.jgrapht.graph.SimpleGraph;
import org.jgrapht.nio.json.JSONExporter;
import org.jgrapht.nio.json.JSONImporter;
import org.jgrapht.util.SupplierUtil;
import java.io.*;
import java.nio.charset.StandardCharsets;
public class GraphSerializationExample {
public static void main(String[] args) {
//Create a simple undirected graph
Graph<String, DefaultEdge> graph = createGraph();
//Serialize the graph into JSON format and save it to a file
serializeGraph(graph, "graph.json");
//Deserialize Graph from File
Graph<String, DefaultEdge> deserializedGraph = deserializeGraph("graph.json");
//Print Deserialized Graph
System. out. println ("Deserialized graph:");
System.out.println(deserializedGraph);
}
private static Graph<String, DefaultEdge> createGraph() {
Graph<String, DefaultEdge> graph = new SimpleGraph<>(SupplierUtil.createStringSupplier(), SupplierUtil.createDefaultEdgeSupplier());
graph.addVertex("A");
graph.addVertex("B");
graph.addVertex("C");
graph.addEdge("A", "B");
graph.addEdge("B", "C");
graph.addEdge("C", "A");
return graph;
}
private static void serializeGraph(Graph<String, DefaultEdge> graph, String fileName) {
JSONExporter<String, DefaultEdge> exporter = new JSONExporter<>();
Writer writer;
try {
writer = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(fileName), StandardCharsets.UTF_8));
exporter.exportGraph(graph, writer);
writer.close();
} catch (IOException e) {
e.printStackTrace();
}
}
private static Graph<String, DefaultEdge> deserializeGraph(String fileName) {
JSONImporter<String, DefaultEdge> importer = new JSONImporter<>();
Graph<String, DefaultEdge> graph = new SimpleGraph<>(SupplierUtil.createStringSupplier(), SupplierUtil.createDefaultEdgeSupplier());
try {
InputStream inputStream = new FileInputStream(fileName);
importer.importGraph(graph, inputStream);
} catch (IOException e) {
e.printStackTrace();
}
return graph;
}
}
In the above code, we first created a simple undirected graph, and then serialized the graph into JSON format by calling the 'serializeGraph' function and saved it to a file. Next, we use the 'deserializeGraph' function to deserialize the graph from the file and print the results.
Finally, by running the program, we can see the results of the deserialized graph output to the console.
Summary: By using the JGraphT library, we can easily implement graph serialization and deserialization operations. This library provides an easy-to-use and powerful API that can help us handle various types of graph data structures. In the sample code, we used the JSONExporter and JSONImporter provided by JGraphT to serialize and deserialize graphs, and also demonstrated how to create, manipulate, and print graph objects.
