英文:
Consume the results of Neo4j driver in java
问题
使用Neo4j Java驱动程序，我想向数据库发送一个搜索查询，类似于：
MATCH(a:`Label`{Property:"NODE_PROPERTY"})
RETURN *
首先，我创建一个会话，然后使用驱动程序的run方法运行查询：
Result run = session.run(query);
run变量包含一系列记录（Records）。我的问题是如何消耗这些记录，以便我可以将它们转换为Java对象？我尝试过获取结果的值，但由于它们不可迭代，无法逐个获取。
英文:
Using Neo4j driver for java, i want to send a search query to the database such as:
MATCH(a:`Label`{Property:"NODE_PROPERTY"})
RETURN *
First i create a session and the i use the run methods of the driver to run a query:
Result run = session.run(query);
run variable contains a list of Records. My question is how can i consume the records so that i can convert them to java objects? I tried to get the values of the results but since they're not iterable, it's not possible to get them one by one.
答案1
得分: 1
Result 实现了 Iterator<Record> 接口，因此有许多方法可以使用它，例如：
While 循环（Java 6 风格）：
Result result = session.run(query);
List<MyPojo> myList = new ArrayList<>();
while(result.hasNext()) {
Record r = result.next();
myList.add(mapToMyPojo(r));
}
流式操作（Java 8+ 风格）：
Result result = session.run(query);
List<MyPojo> myList = result.stream()
.map(record -> mapToMyPojo(record))
.collect(Collectors.toList());
使用 Result.list(Function<Record,T> mapFunction)：
Result result = session.run(query);
List<MyPojo> myList = result.list(r -> mapToMyPojo(r));
将结果映射到 Java 对象非常直观：
public MyPojo mapToMyPojo(Record record) {
MyPojo pojo = new MyPojo();
pojo.setProperty(record.get("Property").asString());
// ...
return pojo;
}
虽然您可以手动映射结果，但也可以考虑使用 neo4j-ogm。
英文:
Result implements Iterator<Record>, so there is a bunch of ways of consuming it, e.g.:
While loop (Java 6 style):
Result result = session.run(query);
List<MyPojo> myList = new ArrayList<>();
while(result.hasNext()) {
Record r = result.next();
myList.add(mapToMyPojo(r));
}
Stream (Java 8+ style):
Result result = session.run(query);
List<MyPojo> myList = result.stream()
.map(record -> mapToMyPojo(record))
.collect(Collectors.toList());
Using Result.list(Function<Record,T> mapFunction):
Result result = session.run(query);
List<MyPojo> myList = result.list(r -> mapToMyPojo(r));
Mapping to a Java object is pretty stright-forward:
public MyPojo mapToMyPojo(Record record) {
MyPojo pojo = new MyPojo();
pojo.setProperty(record.get("Property").asString());
// ...
return pojo;
}
Although instead of mapping results manually, you might want to use neo4j-ogm
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