JsonMappingException: No suitable constructor found for type [simple type, class ]: can not instantiate from JSON object
I am getting the following error “no suitable constructor found for type” when trying to get a JSON request and process it:
org.codehaus.jackson.map.JsonMappingException: No suitable constructor found for type [simple type, class com.myweb.ApplesDO]: can not instantiate from a JSON object (need to add/enable type information?)
Here is the JSON I am trying to send:
{
"applesDO" : [
{
"apple" : "Green Apple"
},
{
"apple" : "Red Apple"
}
]
}
In Controller, I have the following method signature:
@RequestMapping("showApples.do")
public String getApples(@RequestBody final AllApplesDO applesRequest){
// Method Code
}
AllApplesDO is a wrapper of ApplesDO :
public class AllApplesDO {
private ListapplesDO; public ListgetApplesDO() { return applesDO;
}
public void setApplesDO(ListapplesDO) { this.applesDO = applesDO;
}
}
ApplesDO:
public class ApplesDO {
private String apple;
public String getApple() {
return apple;
}
public void setApple(String appl) {
this.apple = apple;
}
public ApplesDO(CustomType custom){
//constructor Code
}
}
I think that Jackson is unable to convert JSON into Java objects for subclasses. Please help with the configuration parameters for Jackson to convert JSON into Java Objects. I am using Spring Framework.
EDIT: Included the major bug that is causing this problem in the above sample class - Please look accepted answer for a solution.
The problem isn't with the Jackson configuration
Actually, the obstacle was in ApplesDO Class:
public class ApplesDO {
private String apple;
public String getApple() {
return apple;
}
public void setApple(String apple) {
this.apple = apple;
}
public ApplesDO(CustomType custom) {
//constructor Code
}
}There was a custom constructor set for the class executing it the default constructor. Preceding a dummy constructor has made the failure to go away:
public class ApplesDO {
private String apple;
public String getApple() {
return apple;
}
public void setApple(String apple) {
this.apple = apple;
}
public ApplesDO(CustomType custom) {
//constructor Code
}
//Introducing the dummy constructor
public ApplesDO() {
}
}