用杰克逊写yaml？

Question

我使用Jackson来阅读和修改yaml文件。效果很好。但是，我无法找到编写yaml所需的神奇咒语。

ObjectMapper mapper = new ObjectMapper(new YAMLFactory());
ObjectNode root = (ObjectNode)mapper.readTree(yamlFileIn);
// modify root here
mapper.writeValue(yamlFileOut, root); // writes json, not yaml. not sure why.

我确定它是作家，JsonGenerators和其他东西的组合。有人拿到样本代码吗？

Answer 1

对于v2.8.3，以下内容应该有效：

YAMLFactory yf = new YAMLFactory();
ObjectMapper mapper = new ObjectMapper(yf);
ObjectNode root = (ObjectNode) mapper.readTree(yamlFileIn);
// modify root here     
FileOutputStream fos = new FileOutputStream(yamlFileOut);
SequenceWriter sw = mapper.writerWithDefaultPrettyPrinter().writeValues(fos);
sw.write(root);

Answer 2

尝试：

YAMLFactory yf = new YAMLFactory();
ObjectMapper mapper = new ObjectMapper(yf);
ObjectNode root = (ObjectNode) mapper.readTree(yamlFileIn);
// modify root here     
FileOutputStream fos = new FileOutputStream(yamlFileOut);
yf.createGenerator(fos).writeObject(root); // works. yay.