我有两个使用Hibernate @OneToMany映射的域模型。我试图在前端创建一个JSON对象，并将其发送到spring mvc控制器以自行设置模型数据。
以下是我的模型课程：
ConceptModelDetails.java
@Entity
@Table(name="conceptModelDetails")
@SequenceGenerator(name="CONCEPT_SEQ",sequenceName="concept_sequence", initialValue=1, allocationSize=1)
public class ConceptModelDetails implements java.io.Serializable{
private static final long serialVersionUID = 1L;
@Id @GeneratedValue(strategy = GenerationType.SEQUENCE, generator="CONCEPT_SEQ")
private int instructionsId;
private String operationType;
private String conceptModelID;
private String requestor;
private String status;
private Timestamp requestDateTime;
private Timestamp lastExecutedDateTime;
private Timestamp completedDateTime;
@OneToMany(fetch = FetchType.EAGER, cascade=CascadeType.ALL, mappedBy="conceptModelDetails")
@JsonManagedReference // nested exception is org.springframework.http.converter.HttpMessageNotWritableException:
//Could not write JSON: Infinite recursion
//The fix is to get Jackson to be able to handle bi-directional references
private List<Instructions> instructions = new ArrayList<Instructions>();
public ConceptModelDetails() {
// TODO Auto-generated constructor stub
}
//setter & getter methods
}
和Instructions.java：
@Entity
@Table(name="instructions")
@SequenceGenerator(name="INSTRUCTIONS_SEQ", sequenceName="instructions_sequence",initialValue=1, allocationSize=1)
public class Instructions implements java.io.Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator="INSTRUCTIONS_SEQ")
private int Sno;
private String instruction;
@ManyToOne
@JoinColumn(name="instructionsId")
@JsonBackReference
private ConceptModelDetails conceptModelDetails;
//setter & getter methods
}
这是我在前端创建和发送JSON对象的send方法：
$scope.send = function() {
console.log("test");
var dataObj = {
"operationType" : $scope.operationType,
"conceptModelID" : $scope.conceptID,
"requestor" : $scope.requestor,
"status" : "new",
"requestDateTime" : null,
"lastExecutedDateTime" : null,
"completedDateTime" : null,
"instructions" : null
};
console.log(dataObj);
dataObj.instructions = [];
console.log($scope.operations_publish);
var ins = getSelected();
for ( var i in ins) {
var temp = {
instruction : null,
conceptModelDetails : null
}
temp.instruction = ins[i];
dataObj.instructions.push(temp);
}
var response = $http.post(
'PostService', dataObj);
response.success(function(data, status, headers, config) {
$scope.responseData = data;
});
response.error(function(data, status, headers, config) {
alert("Exception details: " + JSON.stringify({
data : data
}));
});
}
以下是我的控制器：
@RequestMapping(value = "/PostService", method = RequestMethod.POST)
public @ResponseBody String Test(@RequestBody ConceptModelDetails conceptModelDetails){
ApplicationContext context = new ClassPathXmlApplicationContext(
"applicationContext.xml");
ConceptModelDAO obj = (ConceptModelDAO) context.getBean("objDAO");
System.out.println("concept id: "+conceptModelDetails.getConceptModelID()+" "+ conceptModelDetails.getInstructionsId());
System.out.println("instructions id: "+conceptModelDetails.getInstructions());
// ConceptModelDAOImpl objDAO = new ConceptModelDAOImpl();
obj.add(conceptModelDetails);
Instructions instructions = new Instructions();
System.out.println("dimba: " + instructions.getInstruction());
ArrayList<Instructions> operations = (ArrayList<Instructions>) conceptModelDetails.getInstructions();
for (int i = 0; i< operations.size(); i++ ) {
instructions.setInstruction(operations.get(i).getInstruction());
instructions.setConceptModelDetails(conceptModelDetails);
obj.addInstructions(instructions);
}
return null;
}
我得到的错误是：
List<Instructions> instructions是400（错误请求）。请提出我该如何处理。 最佳答案
我在此代码中发现了问题。如Bozho here所述，ArrayList<Instructions> operations = (ArrayList<Instructions>) conceptModelDetails.getInstructions();
应该List<Instructions> operations = conceptModelDetails.getInstructions();
在弹簧控制器中。