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Maven pom dependency
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.9.8</version>
</dependency>
- jackson-annotations-2.9.8.jar
- jackson-core-2.9.8.jar
- jackson-databind-2.9.8.jar
Example - Convert JSON string to Map
JacksonJsonToMap.java
package net.javaguides.jackson;
import java.io.IOException;
import java.util.Map;
import java.util.Map.Entry;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;
public class JacksonJsonToMap {
public static void main(String[] args) throws IOException {
ObjectMapper mapper = new ObjectMapper();
mapper.enable(SerializationFeature.INDENT_OUTPUT);
String json = "{" +
" \"THU\" : 5," +
" \"TUE\" : 3," +
" \"WED\" : 4," +
" \"SAT\" : 7," +
" \"FRI\" : 6," +
" \"MON\" : 2," +
" \"SUN\" : 1" +
"}";
@SuppressWarnings("unchecked")
Map < String, Integer > days = mapper.readValue(json, Map.class);
for (Entry < String, Integer > day: days.entrySet()) {
System.out.println(day.getKey() + "=" + day.getValue());
}
}
}
Output:
THU=5
TUE=3
WED=4
SAT=7
FRI=6
MON=2
SUN=1
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