package neo4j;
import java.io.File;
import java.io.IOException;
import javax.management.relation.Relation;
import org.neo4j.graphdb.GraphDatabaseService;
import org.neo4j.graphdb.Node;
import org.neo4j.graphdb.Relationship;
import org.neo4j.graphdb.RelationshipType;
import org.neo4j.graphdb.Transaction;
import org.neo4j.graphdb.factory.GraphDatabaseFactory;
import org.neo4j.io.fs.FileUtils;
public class test {
public enum RelTypes implements RelationshipType{
KNOWS }
private static void registerShutdownHook( final GraphDatabaseService graphDb ) {
// Registers a shutdown hook for the Neo4j instance so that it // shuts down nicely when the VM exits (even if you "Ctrl-C" the // running example before it's completed) /*为了确保neo4j数据库的正确关闭，我们可以添加一个关闭钩子方法 * registerShutdownHook。这个方法的意思就是在jvm中增加一个关闭的 * 钩子，当jvm关闭的时候，会执行系统中已经设置的所有通过方法 * addShutdownHook添加的钩子，当系统执行完这些钩子后，jvm才会关闭。 * 所以这些钩子可以在jvm关闭的时候进行内存清理、对象销毁等操作。*/ Runtime.getRuntime().addShutdownHook( new Thread() {
@Override public void run() {
graphDb.shutdown();
}
}
);
}
public static void main(String[] args) throws IOException {
FileUtils.deleteRecursively( new File( "db" ) );
GraphDatabaseService graphdb=new GraphDatabaseFactory().newEmbeddedDatabase("db");
Relationship relationship;
Transaction tx=graphdb.beginTx();
try{
Node node1=graphdb.createNode();
Node node2=graphdb.createNode();
node1.setProperty("message", "Hello");
node2.setProperty("message", "World");
relationship = node1.createRelationshipTo(node2, RelTypes.KNOWS);
relationship.setProperty("message", "brave neo4j");
tx.success();
System.out.println("successfully");
}
finally{
tx.finish();
}
registerShutdownHook(graphdb);
}
}