Mixing
List and java.lang.ClassCastException: com.google.gson.internal.StringMap
0
Below my function,
public <T> List<T> jsonToListBean(String json, Class<T> clazz) {
Gson gson = new Gson();
Type listType = new TypeToken<List<T>>(){}.getType();
List<T> returnValue = gson.fromJson(json, listType);
return returnValue;
}
but the system returns this exception:
java.lang.ClassCastException: com.google.gson.internal.StringMap
I notice also that if I use the following line code
Type listType = new TypeToken<ArrayList<ShapeBean>>(){}.getType();
it works, but my target is to be absolutly as generic as possible to make my code more efficient.
How should i change my code to make usable also passing the type "T" instead the "ShapeBean"?
java json gson javabeans classcastexception
asked Nov 19 '18 at 14:26
rugby82
159214
add a comment |
0
Below my function,
public <T> List<T> jsonToListBean(String json, Class<T> clazz) {
Gson gson = new Gson();
Type listType = new TypeToken<List<T>>(){}.getType();
List<T> returnValue = gson.fromJson(json, listType);
return returnValue;
}
but the system returns this exception:
java.lang.ClassCastException: com.google.gson.internal.StringMap
I notice also that if I use the following line code
Type listType = new TypeToken<ArrayList<ShapeBean>>(){}.getType();
it works, but my target is to be absolutly as generic as possible to make my code more efficient.
How should i change my code to make usable also passing the type "T" instead the "ShapeBean"?
java json gson javabeans classcastexception
asked Nov 19 '18 at 14:26
rugby82
159214
I'm not really familiar with GSON but you could try to implement some method ofTypeTokenthat makes use ofclazzor createlistTypeyourself. One thing we're doing with Jackson isClass<? extends Object> arrayClass = Array.newInstance( clazz, 0 ).getClass(),passarrayClassto Jackson and finally returnArrays.asList( parsedArray )whereparsedArrayis what Jackson returns. Something similar might be possible with GSON - if you need that fallback.
– Thomas
Nov 19 '18 at 14:34
1
Possible duplicate of Gson TypeToken with dynamic ArrayList item type
– kan
Nov 19 '18 at 14:42
it does not solve my problem
– rugby82
Nov 19 '18 at 14:53
How you are callingjsonToListBean(..)?
– Ashish Patil
Nov 19 '18 at 15:04
List<ShapeBean> listaBean = jsonToListBean(jsonMessage, ShapeBean.class);
– rugby82
Nov 19 '18 at 15:28
add a comment |
0
0
0
Below my function,
public <T> List<T> jsonToListBean(String json, Class<T> clazz) {
Gson gson = new Gson();
Type listType = new TypeToken<List<T>>(){}.getType();
List<T> returnValue = gson.fromJson(json, listType);
return returnValue;
}
but the system returns this exception:
java.lang.ClassCastException: com.google.gson.internal.StringMap
I notice also that if I use the following line code
Type listType = new TypeToken<ArrayList<ShapeBean>>(){}.getType();
it works, but my target is to be absolutly as generic as possible to make my code more efficient.
How should i change my code to make usable also passing the type "T" instead the "ShapeBean"?
java json gson javabeans classcastexception
asked Nov 19 '18 at 14:26
rugby82
159214
Below my function,
public <T> List<T> jsonToListBean(String json, Class<T> clazz) {
Gson gson = new Gson();
Type listType = new TypeToken<List<T>>(){}.getType();
List<T> returnValue = gson.fromJson(json, listType);
return returnValue;
}
but the system returns this exception:
java.lang.ClassCastException: com.google.gson.internal.StringMap
I notice also that if I use the following line code
Type listType = new TypeToken<ArrayList<ShapeBean>>(){}.getType();
it works, but my target is to be absolutly as generic as possible to make my code more efficient.
How should i change my code to make usable also passing the type "T" instead the "ShapeBean"?
java json gson javabeans classcastexception
java json gson javabeans classcastexception
asked Nov 19 '18 at 14:26
rugby82
159214
asked Nov 19 '18 at 14:26
rugby82
159214
edited Nov 19 '18 at 15:40
asked Nov 19 '18 at 14:26
rugby82
159214
asked Nov 19 '18 at 14:26
rugby82
159214
asked Nov 19 '18 at 14:26
rugby82
159214
159214
I'm not really familiar with GSON but you could try to implement some method ofTypeTokenthat makes use ofclazzor createlistTypeyourself. One thing we're doing with Jackson isClass<? extends Object> arrayClass = Array.newInstance( clazz, 0 ).getClass(),passarrayClassto Jackson and finally returnArrays.asList( parsedArray )whereparsedArrayis what Jackson returns. Something similar might be possible with GSON - if you need that fallback.
– Thomas
Nov 19 '18 at 14:34
1
Possible duplicate of Gson TypeToken with dynamic ArrayList item type
– kan
Nov 19 '18 at 14:42
it does not solve my problem
– rugby82
Nov 19 '18 at 14:53
How you are callingjsonToListBean(..)?
– Ashish Patil
Nov 19 '18 at 15:04
List<ShapeBean> listaBean = jsonToListBean(jsonMessage, ShapeBean.class);
– rugby82
Nov 19 '18 at 15:28
add a comment |
I'm not really familiar with GSON but you could try to implement some method ofTypeTokenthat makes use ofclazzor createlistTypeyourself. One thing we're doing with Jackson isClass<? extends Object> arrayClass = Array.newInstance( clazz, 0 ).getClass(),passarrayClassto Jackson and finally returnArrays.asList( parsedArray )whereparsedArrayis what Jackson returns. Something similar might be possible with GSON - if you need that fallback.
– Thomas
Nov 19 '18 at 14:34
1
Possible duplicate of Gson TypeToken with dynamic ArrayList item type
– kan
Nov 19 '18 at 14:42
it does not solve my problem
– rugby82
Nov 19 '18 at 14:53
How you are callingjsonToListBean(..)?
– Ashish Patil
Nov 19 '18 at 15:04
List<ShapeBean> listaBean = jsonToListBean(jsonMessage, ShapeBean.class);
– rugby82
Nov 19 '18 at 15:28
I'm not really familiar with GSON but you could try to implement some method of
TypeToken that makes use of clazz or create listType yourself. One thing we're doing with Jackson is Class<? extends Object> arrayClass = Array.newInstance( clazz, 0 ).getClass() ,pass arrayClass to Jackson and finally return Arrays.asList( parsedArray ) where parsedArray is what Jackson returns. Something similar might be possible with GSON - if you need that fallback.– Thomas
Nov 19 '18 at 14:34
I'm not really familiar with GSON but you could try to implement some method of
TypeToken that makes use of clazz or create listType yourself. One thing we're doing with Jackson is Class<? extends Object> arrayClass = Array.newInstance( clazz, 0 ).getClass() ,pass arrayClass to Jackson and finally return Arrays.asList( parsedArray ) where parsedArray is what Jackson returns. Something similar might be possible with GSON - if you need that fallback.– Thomas
Nov 19 '18 at 14:34
1
1
Possible duplicate of Gson TypeToken with dynamic ArrayList item type
– kan
Nov 19 '18 at 14:42
Possible duplicate of Gson TypeToken with dynamic ArrayList item type
– kan
Nov 19 '18 at 14:42
it does not solve my problem
– rugby82
Nov 19 '18 at 14:53
it does not solve my problem
– rugby82
Nov 19 '18 at 14:53
How you are calling
jsonToListBean(..)?– Ashish Patil
Nov 19 '18 at 15:04
How you are calling
jsonToListBean(..)?– Ashish Patil
Nov 19 '18 at 15:04
List<ShapeBean> listaBean = jsonToListBean(jsonMessage, ShapeBean.class);
– rugby82
Nov 19 '18 at 15:28
List<ShapeBean> listaBean = jsonToListBean(jsonMessage, ShapeBean.class);
– rugby82
Nov 19 '18 at 15:28
add a comment |
1 Answer
1
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0
Solved. Thanks to kan's link below the code:
public <T> List<T> listEntity(String jsonCommand, Class<T> clazz) {
List<T> lst = new ArrayList<T>();
try {
// Consuming remote method
JsonParser parser = new JsonParser();
JsonArray array = parser.parse(jsonCommand).getAsJsonArray();
for(final JsonElement json: array){
Gson g = new Gson();
T entity = g.fromJson(json, clazz);
lst.add(entity);
}
} catch (Exception e) {
e.printStackTrace();
} return lst;
}
check also this:
Gson TypeToken with dynamic ArrayList item type
answered Nov 20 '18 at 13:53
rugby82
159214
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
0
Solved. Thanks to kan's link below the code:
public <T> List<T> listEntity(String jsonCommand, Class<T> clazz) {
List<T> lst = new ArrayList<T>();
try {
// Consuming remote method
JsonParser parser = new JsonParser();
JsonArray array = parser.parse(jsonCommand).getAsJsonArray();
for(final JsonElement json: array){
Gson g = new Gson();
T entity = g.fromJson(json, clazz);
lst.add(entity);
}
} catch (Exception e) {
e.printStackTrace();
} return lst;
}
check also this:
Gson TypeToken with dynamic ArrayList item type
answered Nov 20 '18 at 13:53
rugby82
159214
add a comment |
0
Solved. Thanks to kan's link below the code:
public <T> List<T> listEntity(String jsonCommand, Class<T> clazz) {
List<T> lst = new ArrayList<T>();
try {
// Consuming remote method
JsonParser parser = new JsonParser();
JsonArray array = parser.parse(jsonCommand).getAsJsonArray();
for(final JsonElement json: array){
Gson g = new Gson();
T entity = g.fromJson(json, clazz);
lst.add(entity);
}
} catch (Exception e) {
e.printStackTrace();
} return lst;
}
check also this:
Gson TypeToken with dynamic ArrayList item type
answered Nov 20 '18 at 13:53
rugby82
159214
add a comment |
0
0
0
Solved. Thanks to kan's link below the code:
public <T> List<T> listEntity(String jsonCommand, Class<T> clazz) {
List<T> lst = new ArrayList<T>();
try {
// Consuming remote method
JsonParser parser = new JsonParser();
JsonArray array = parser.parse(jsonCommand).getAsJsonArray();
for(final JsonElement json: array){
Gson g = new Gson();
T entity = g.fromJson(json, clazz);
lst.add(entity);
}
} catch (Exception e) {
e.printStackTrace();
} return lst;
}
check also this:
Gson TypeToken with dynamic ArrayList item type
answered Nov 20 '18 at 13:53
rugby82
159214
Solved. Thanks to kan's link below the code:
public <T> List<T> listEntity(String jsonCommand, Class<T> clazz) {
List<T> lst = new ArrayList<T>();
try {
// Consuming remote method
JsonParser parser = new JsonParser();
JsonArray array = parser.parse(jsonCommand).getAsJsonArray();
for(final JsonElement json: array){
Gson g = new Gson();
T entity = g.fromJson(json, clazz);
lst.add(entity);
}
} catch (Exception e) {
e.printStackTrace();
} return lst;
}
check also this:
Gson TypeToken with dynamic ArrayList item type
answered Nov 20 '18 at 13:53
rugby82
159214
answered Nov 20 '18 at 13:53
rugby82
159214
answered Nov 20 '18 at 13:53
rugby82
159214
answered Nov 20 '18 at 13:53
rugby82
159214
159214
add a comment |
add a comment |
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I'm not really familiar with GSON but you could try to implement some method of
TypeTokenthat makes use ofclazzor createlistTypeyourself. One thing we're doing with Jackson isClass<? extends Object> arrayClass = Array.newInstance( clazz, 0 ).getClass(),passarrayClassto Jackson and finally returnArrays.asList( parsedArray )whereparsedArrayis what Jackson returns. Something similar might be possible with GSON - if you need that fallback.– Thomas
Nov 19 '18 at 14:34
1
Possible duplicate of Gson TypeToken with dynamic ArrayList item type
– kan
Nov 19 '18 at 14:42
it does not solve my problem
– rugby82
Nov 19 '18 at 14:53
How you are calling
jsonToListBean(..)?– Ashish Patil
Nov 19 '18 at 15:04
List<ShapeBean> listaBean = jsonToListBean(jsonMessage, ShapeBean.class);
– rugby82
Nov 19 '18 at 15:28