Reputation: 298
I have more than one class that I want to serialize using Jackson to generate Json, for example
public class A{
int id;
String name;
Object database;
... getter and setter
}
I need to encode all value of the json to base64, so I configure the object mapper like this
public class Base64Serializer<T> extends StdSerializer<T> {
private static final long serialVersionUID = 1L;
protected Base64Serializer(Class<?> t, boolean f) {
super(t, f);
}
@Override
public void serialize(T value, JsonGenerator jsonGenerator, SerializerProvider arg2) throws IOException {
String ecnodedOutput = Base64.getEncoder().encodeToString(((String) value).getBytes());
jsonGenerator.writeString(ecnodedOutput);
}
}
//Using the base64 Serializer to configure Object mapper
SimpleModule module = new SimpleModule();
module.addSerializer(new Base64Serializer(String.class, false));
objectMapper.registerModule(module);
objectMapper.writerWithDefaultPrettyPrinter().writeValue(outputStream,intanceOfClassA);
The problem is it's only encode the String type as the serializer only accept one type, is there any method to encode all field values, (long, int, object, etc..) I mean to encode all value of the json field regarding it type of string or int??
Upvotes: 2
Views: 2086
Reputation: 702
Just in case if someone is looking for converting any kind of object to Base64 string using something like Jackson or Gson. You could do something like this:
Convert your object to string using Jackson/Gson:
str = objectMapper.writeValueAsString(obj) OR str = gson.toJson(obj)
Now you get bytes from your string using
base64str = str.getBytes()
Use java's Base64 class to convert bytes to Base64 string:
Base64.getEncoder().encodeToString(base64str)
Upvotes: 0
Reputation: 3572
You could use following:
Serializer
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.util.Base64;
public class Base64Serializer<T extends Serializable> extends StdSerializer<T> {
private static final long serialVersionUID = 1L;
protected Base64Serializer(Class<?> t, boolean f) {
super(t, f);
}
@Override
public void serialize(T value, JsonGenerator jsonGenerator, SerializerProvider arg2) throws IOException {
String ecnodedOutput = Base64.getEncoder().encodeToString(serialize(value));
jsonGenerator.writeString(ecnodedOutput);
}
public static byte[] serialize(Object obj) throws IOException {
ByteArrayOutputStream out = new ByteArrayOutputStream();
ObjectOutputStream os = new ObjectOutputStream(out);
os.writeObject(obj);
return out.toByteArray();
}
}
Registration and test:
public class SerializerTest {
public static void main(String[] args) throws JsonProcessingException {
ObjectMapper objectMapper = new ObjectMapper();
SimpleModule module = new SimpleModule();
addSerializers(module, Serializable.class, int.class, double.class, float.class, char.class, byte.class, short.class);
objectMapper.registerModule(module);
System.out.println(objectMapper.writeValueAsString(new A(10, "test", Arrays.asList(10000L, "TTTT2"))));
}
private static void addSerializers(SimpleModule module, Class... classes) {
Arrays.stream(classes).forEach(c -> module.addSerializer(new Base64Serializer(c, false)));
}
}
Output:
{
"id": "rO0ABXNyABFqYXZhLmxhbmcuSW50ZWdlchLioKT3gYc4AgABSQAFdmFsdWV4cgAQamF2YS5sYW5nLk51bWJlcoaslR0LlOCLAgAAeHAAAAAK",
"name": "rO0ABXQABHRlc3Q=",
"database": "rO0ABXNyABpqYXZhLnV0aWwuQXJyYXlzJEFycmF5TGlzdNmkPL7NiAbSAgABWwABYXQAE1tMamF2YS9sYW5nL09iamVjdDt4cHVyABdbTGphdmEuaW8uU2VyaWFsaXphYmxlO67QCaxT1+1JAgAAeHAAAAACc3IADmphdmEubGFuZy5Mb25nO4vkkMyPI98CAAFKAAV2YWx1ZXhyABBqYXZhLmxhbmcuTnVtYmVyhqyVHQuU4IsCAAB4cAAAAAAAACcQdAAFVFRUVDI="
}
Upvotes: 2