@Test
public void exampleQuery() throws Exception {
// START SNIPPET: JavaQuery
ExecutionEngine engine = new ExecutionEngine(db);
ExecutionResult result = engine.execute("start n=node(0) where 1=1 return n");
assertThat(result.columns(), hasItem("n"));
Iterator<Node> n_column = result.columnAs("n");
assertThat(asIterable(n_column), hasItem(db.getNodeById(0)));
assertThat(result.toString(), containsString("Node[0]"));
// END SNIPPET: JavaQuery
}
@Test
@Graph(
value = {"John friend Sara", "John friend Joe", "Sara friend Maria", "Joe friend Steve"},
autoIndexNodes = true)
public void intro_examples() throws Exception {
try (Transaction ignored = graphdb.beginTx()) {
Writer fw = AsciiDocGenerator.getFW(DOCS_TARGET, gen.get().getTitle());
data.get();
fw.append("\nImagine an example graph like the following one:\n\n");
fw.append(
AsciiDocGenerator.dumpToSeparateFileWithType(
new File(DOCS_TARGET),
"intro.graph",
AsciidocHelper.createGraphVizWithNodeId("Example Graph", graphdb(), "cypher-intro")));
fw.append(
"\nFor example, here is a query which finds a user called John and John's friends (though not "
+ "his direct friends) before returning both John and any friends-of-friends that are found.");
fw.append("\n\n");
String query = "MATCH (john {name: 'John'})-[:friend]->()-[:friend]->(fof) RETURN john, fof ";
fw.append(
AsciiDocGenerator.dumpToSeparateFileWithType(
new File(DOCS_TARGET), "intro.query", createCypherSnippet(query)));
fw.append("\nResulting in:\n\n");
fw.append(
AsciiDocGenerator.dumpToSeparateFileWithType(
new File(DOCS_TARGET),
"intro.result",
createQueryResultSnippet(engine.execute(query).dumpToString())));
fw.append(
"\nNext up we will add filtering to set more parts "
+ "in motion:\n\nWe take a list of user names "
+ "and find all nodes with names from this list, match their friends and return "
+ "only those followed users who have a +name+ property starting with +S+.");
query =
"MATCH (user)-[:friend]->(follower) WHERE "
+ "user.name IN ['Joe', 'John', 'Sara', 'Maria', 'Steve'] AND follower.name =~ 'S.*' "
+ "RETURN user, follower.name ";
fw.append("\n\n");
fw.append(
AsciiDocGenerator.dumpToSeparateFileWithType(
new File(DOCS_TARGET), "intro.query", createCypherSnippet(query)));
fw.append("\nResulting in:\n\n");
fw.append(
AsciiDocGenerator.dumpToSeparateFileWithType(
new File(DOCS_TARGET),
"intro.result",
createQueryResultSnippet(engine.execute(query).dumpToString())));
fw.close();
}
}
@Test
public void shouldBeAbleToEmitJavaIterables() throws Exception {
makeFriends(michaelaNode, andreasNode);
makeFriends(michaelaNode, johanNode);
ExecutionEngine engine = new ExecutionEngine(db);
ExecutionResult result =
engine.execute("start n=node(0) match n-->friend return collect(friend)");
Iterable<Node> friends = (Iterable<Node>) result.columnAs("collect(friend)").next();
assertThat(friends, hasItems(andreasNode, johanNode));
assertThat(friends, instanceOf(Iterable.class));
}
@Test
public void exampleWithParametersForQuery() throws Exception {
// START SNIPPET: exampleWithParametersForQuery
Map<String, Object> params = new HashMap<String, Object>();
params.put("query", "name:Andreas");
ExecutionResult result = engine.execute("start n=node:people({query}) return n", params);
// END SNIPPET: exampleWithParametersForQuery
assertEquals(asList(andreasNode), this.<Node>toList(result, "n"));
}
@Test
public void exampleWithParameterForMultipleNodeIds() throws Exception {
// START SNIPPET: exampleWithParameterForMultipleNodeIds
Map<String, Object> params = new HashMap<String, Object>();
params.put("id", Arrays.asList(0, 1, 2));
ExecutionResult result = engine.execute("start n=node({id}) return n.name", params);
// END SNIPPET: exampleWithParameterForMultipleNodeIds
assertEquals(asList("Michaela", "Andreas", "Johan"), this.<String>toList(result, "n.name"));
}
@Test
public void exampleWithStringLiteralAsParameter() throws Exception {
// START SNIPPET: exampleWithStringLiteralAsParameter
Map<String, Object> params = new HashMap<String, Object>();
params.put("name", "Johan");
ExecutionResult result =
engine.execute("start n=node(0,1,2) where n.name = {name} return n", params);
// END SNIPPET: exampleWithStringLiteralAsParameter
assertEquals(asList(johanNode), this.<Node>toList(result, "n"));
}
@Test
public void exampleWithParameterForNodeObject() throws Exception {
// START SNIPPET: exampleWithParameterForNodeObject
Map<String, Object> params = new HashMap<String, Object>();
params.put("node", andreasNode);
ExecutionResult result = engine.execute("start n=node({node}) return n.name", params);
// END SNIPPET: exampleWithParameterForNodeObject
assertThat(result.columns(), hasItem("n.name"));
Iterator<Object> n_column = result.columnAs("n.name");
assertEquals("Andreas", n_column.next());
}
@Test
public void exampleWithParametersForIndexKeyAndValue() throws Exception {
// START SNIPPET: exampleWithParametersForIndexKeyAndValue
Map<String, Object> params = new HashMap<String, Object>();
params.put("key", "name");
params.put("value", "Michaela");
ExecutionResult result =
engine.execute("start n=node:people({key} = {value}) return n", params);
// END SNIPPET: exampleWithParametersForIndexKeyAndValue
assertEquals(asList(michaelaNode), this.<Node>toList(result, "n"));
}
@Test
public void testColumnAreInTheRightOrder() throws Exception {
createTenNodes();
String q =
"start one=node(1), two=node(2), three=node(3), four=node(4), five=node(5), six=node(6), "
+ "seven=node(7), eight=node(8), nine=node(9), ten=node(10) "
+ "return one, two, three, four, five, six, seven, eight, nine, ten";
ExecutionResult result = engine.execute(q);
assertThat(
result.toString(),
matchesPattern("one.*two.*three.*four.*five.*six.*seven.*eight.*nine.*ten"));
}
@Test
public void exampleWithParameterRegularExpression() throws Exception {
// START SNIPPET: exampleWithParameterRegularExpression
Map<String, Object> params = new HashMap<String, Object>();
params.put("regex", ".*h.*");
ExecutionResult result =
engine.execute("start n=node(0,1,2) where n.name =~ {regex} return n.name", params);
// END SNIPPET: exampleWithParameterRegularExpression
assertThat(result.columns(), hasItem("n.name"));
Iterator<Object> n_column = result.columnAs("n.name");
assertEquals("Michaela", n_column.next());
assertEquals("Johan", n_column.next());
}
@Test
public void exampleWithParameterForSkipAndLimit() throws Exception {
// START SNIPPET: exampleWithParameterForSkipLimit
Map<String, Object> params = new HashMap<String, Object>();
params.put("s", 1);
params.put("l", 1);
ExecutionResult result =
engine.execute("start n=node(0,1,2) return n.name skip {s} limit {l}", params);
// END SNIPPET: exampleWithParameterForSkipLimit
assertThat(result.columns(), hasItem("n.name"));
Iterator<Object> n_column = result.columnAs("n.name");
assertEquals("Andreas", n_column.next());
}
/**
* Execution process is done in this method
*
* @throws AppFactoryQueueException
*/
public void execute() throws Exception {
// Running this loop to poll and execute the item from the queue.
while (true && !isProcessStopped) {
// Poll the item from the queue. If the queue is empty, this
// call wait until an item is come to the queue.
T t = executionEngine.getSynchQueue().poll();
log.info("ExecuteEngine Execute an element. Element Info : " + t.toString());
executionEngine.getExecutor().execute(t);
// Waiting a specific time interval before poll again from the
// queue. Default is 0.
if (executionEngine.getCallDelay() > 0) {
try {
Thread.sleep(executionEngine.getCallDelay());
} catch (Exception e) {
String errorMsg = "Error occured in thread sleep, " + e.getMessage();
log.error(errorMsg, e);
}
}
}
}
@Test
public void shouldCloseTransactionsWhenIteratingOverSingleColumn() throws Exception {
// Given an execution result that has been started but not exhausted
createNode();
createNode();
ExecutionResult executionResult = engine.execute("MATCH (n) RETURN n");
ResourceIterator<Node> resultIterator = executionResult.columnAs("n");
resultIterator.next();
assertThat(activeTransaction(), is(notNullValue()));
// When
resultIterator.close();
// Then
assertThat(activeTransaction(), is(nullValue()));
}
