Jackson json to objects

Question

I can't for the life of me figure out how to parse this json file into objects using jackson.

Here is my json file:

 {
 "file": "phrases",
 "use": "quotes",
 "famous_phrases": [
 {
 "phrase1": "one for all",
 "phrase2": "all for one",
 "id": 1
 },
 {
 "phrase1": "four scores",
 "phrase2": "and seven years ago",
 "id": 17
 },
 {
 "phrase1": "elementary",
 "phrase2": "my dear watson",
 "id": 22
 }
 ]
 }

I tried this:

BufferedReader fileReader = new BufferedReader(new FileReader("./test.json"));
ObjectMapper mapper = new ObjectMapper();
JsonNode quotes = mapper.readValue(fileReader, JsonNode.class);
quotes = quotes.get("famous_phrases");
TypeReference<List<Quotes>> phrases = new TypeReference<List<Quotes>>(){};
List<Quotes> q = mapper.readValue(quotes.traverse(), phrases);
for (Phrases element : q) {
 System.out.println(element.getPhrase1());
}

With a POJO I made but I think I might have made the POJO incorrectly. I defined all the attributes (file, use, famous_phrases) and each one had its own set and get methods. Any help into this would be appreciated!

• JB Nizet: What you have there is not valid JSON. It contains 2 JSON objects separated by a comma. So you can't parse it.
• Bozho: How did you obtain the json?
• imakeitrayne: Oh, I received it from a friend who needed it parsed. I will try and add the {} for the whole file. First time using JSON and so I am not too bright on it.

Answer 1

json file:

{
 "file": "phrases",
 "use": "quotes",
 "famous_phrases": [
 {
 "phrase1": "one for all",
 "phrase2": "all for one",
 "id": 1
 },
 {
 "phrase1": "four scores",
 "phrase2": "and seven years ago",
 "id": 17
 },
 {
 "phrase1": "elementary",
 "phrase2": "my dear watson",
 "id": 22
 }
 ]
}

Beans:

public class Quotes {
 private String file;
 private String use;
 private List<Phrases> famous_phrases;
 public String getFile() {
 return file;
 }
 public void setFile(String file) {
 this.file = file;
 }
 public String getUse() {
 return use;
 }
 public void setUse(String use) {
 this.use = use;
 }
 public List<Phrases> getFamous_phrases() {
 return famous_phrases;
 }
 public void setFamous_phrases(List<Phrases> famous_phrases) {
 this.famous_phrases = famous_phrases;
 }
}
public class Phrases {
 private String phrase1;
 private String phrase2;
 private String id;
 public String getPhrase1() {
 return phrase1;
 }
 public void setPhrase1(String phrase1) {
 this.phrase1 = phrase1;
 }
 public String getPhrase2() {
 return phrase2;
 }
 public void setPhrase2(String phrase2) {
 this.phrase2 = phrase2;
 }
 public String getId() {
 return id;
 }
 public void setId(String id) {
 this.id = id;
 }
}

read json file:

BufferedReader fileReader = new BufferedReader(new FileReader("./test.json"));
ObjectMapper mapper = new ObjectMapper();
Quotes quotes = mapper.readValue(fileReader, Quotes.class);
for (Phrases element : quotes.getFamous_phrases()) {
 System.out.println(element.getPhrase1());
}

• imakeitrayne: Thanks, after fixing my json, this works a lot better.

Answer 2

You have to define a root node (wrap your json code with {})

{
 "member1": {
 "file": "phrases",
 "use": "quotes"
 },
 "member2": {
 "famous_phrases": [{
 "phrase1": "one for all",
 "phrase2": "all for one",
 "id": 1
 },
 {
 "phrase1": "four scores",
 "phrase2": "and seven years ago",
 "id": 17
 },
 {
 "phrase1": "elementary",
 "phrase2": "my dear watson",
 "id": 22
 }
 }]
}

• imakeitrayne: Thanks for the help, after seeing my json file was incorrect, this helps a lot as well.