How To Format Json String Inward Coffee - Jackson Event Tutorial

You tin laissez passer notice format JSON String inwards Java using Jackson API's pretty impress feature. As yous mightiness bring noticed inwards my previous JSON tutorials that the output of the programs is non properly formatted, which makes them difficult to read, particularly inwards large log files where in that place are thence many other texts, both JSON too normal text is there. That's why its advised to impress JSON String properly formatted because too thence it volition stand upwards out inwards log file or console. Whenever nosotros impress JSON String from Java Programs past times using method writeValueAsString(), it unremarkably comes inwards i line, equally shown inwards the next event :

{"name":"Virat","sport":"cricket","age":25,"id":121," lastScores":[77,72,23,57,54,36,74,17]}

This is non real readable equally yous cannot run into how many attributes are there, what is their mention too value, compare it to next formatted output which is printed using Jackson's pretty impress feature:

{   "name" : "Virat",  "sport" : "cricket",   "age" : 25,   "id" : 121,   "lastScores" : [ 77, 72, 23, 57, 54, 36, 74, 17 ] }

Its agency improve than before output, it's much to a greater extent than readable. You tin laissez passer notice easily position which i is the only uncomplicated name-value pair, which i is JSON array too much more. Wondering, how to nicely impress JSON String, only banking concern check out the event shown inwards adjacent section.

JSON String Format too Pretty Print Example

In this example, yous volition larn how to format JSON String using Jackson's Pretty Print feature. It's tardily to format JSON text, all yous take away to do is instead of only calling writeValueAsString() yous take away to starting fourth dimension acquire defaultPrettyPrintWrite too and thence telephone phone writeValueAsString() method on that object. This volition ensure that your JSON information volition live nicely printed on console or log file i.e. wherever yous impress it.

import java.io.IOException;  import org.codehaus.jackson.JsonGenerationException; import org.codehaus.jackson.map.JsonMappingException; import org.codehaus.jackson.map.ObjectMapper;  /**  * Java programme to format JSON String using Jackson API. Jackson provides  * dainty pretty impress characteristic to impress JSON text equally formatted output.  *  * @author Javin Paul */ public class JSONPrintDemo{      public static void main(String args[]) {          int[] recentScores = {77, 72, 23, 57, 54, 36, 74, 17};         Player cricketer = new Player("Virat", "cricket", 25, 121,                                           recentScores);          ObjectMapper mapper = new ObjectMapper();          try {             System.out.println("Default JSON String:"                         + mapper.writeValueAsString(cricketer));             System.out.println("formatted JSON String \n"          + mapper.defaultPrettyPrintingWriter().writeValueAsString(cricketer));         } catch (JsonGenerationException e) {             e.printStackTrace();         } catch (JsonMappingException e) {             e.printStackTrace();         } catch (IOException e) {             e.printStackTrace();         }      }  }  class Player {      private String name;     private String sport;     private int age;     private int id;     private int[] lastScores;      public Player(String name, String sport, int age, int id,                       int[] lastinnings) {         this.name = name;         this.sport = sport;         this.age = age;         this.id = id;         lastScores = lastinnings;     }      public final String getName() {         return name;     }      public final String getSport() {         return sport;     }      public final int getAge() {         return age;     }      public final int getId() {         return id;     }      public final int[] getLastScores() {         return lastScores;     }      public final void setName(String name) {         this.name = name;     }      public final void setSport(String sport) {         this.sport = sport;     }      public final void setAge(int age) {         this.age = age;     }      public final void setId(int id) {         this.id = id;     }      public final void setLastScores(int[] lastScores) {         this.lastScores = lastScores;     }      @Override     public String toString() {         return "Player [name=" + mention + ", sport=" + sport                     + ", age=" + historic menses + ", id=" + id + "]";     }  }    Output Default JSON String:{"name":"Virat","sport":"cricket","age":25,                    "id":121,"lastScores":[77,72,23,57,54,36,74,17]} formatted JSON String {   "name" : "Virat",   "sport" : "cricket",   "age" : 25,   "id" : 121,   "lastScores" : [ 77, 72, 23, 57, 54, 36, 74, 17 ] }

Maven Dependency too JAR Files for Jackson

Since Jackson library is non business office of pith Java, yous take away to either specify Maven dependency inwards pom.xml file or yous take away to manually download those Jackson JAR files too position inwards your application's classpath.

<dependency>      <groupId>org.codehaus.jackson</groupId>      <artifactId>jackson-xc</artifactId>      <version>1.9.12</version> </dependency>

JAR files
C:\.m2\repository\org\codehaus\jackson\jackson-xc\1.9.12\jackson-xc-1.9.12.jar
C:\.m2\repository\org\codehaus\jackson\jackson-core-asl\1.9.12\jackson-core-asl-1.9.12.jar
C:\.m2\repository\org\codehaus\jackson\jackson-mapper-asl\1.9.12\jackson-mapper-asl-1.9.12.jar


That's all on how to format JSON String inwards Java using Jackson API's pretty impress facility. This event is real useful piece printing JSON inwards log files to differentiate it from other String outputs. Formatted output non solely stands out inwards logs but equally good they are easier to read but in that place is i drawback also. You cannot grep them inwards i line, yous take away to purpose grep ascendency alongside context selection to grep a twosome of lines only about matching to run into amount JSON output.

Further Reading
Spring Framework 5: Beginner to Guru
Microservices alongside Spring Cloud
Master Java Web Services too REST API alongside Spring Boot

If yous similar this tutorial too desire to larn to a greater extent than most how to bargain alongside JSON inwards Java, delight checkout next amazing Java JSON tutorials  :

• How to parse large JSON document inwards Java? (code example)
• How to read JSON String using json-simple library? (code example)
• How to convert JSON String to Java Object alongside example? (solution)
• How to convert JSON Array to String Array inwards Java? (solution)
• 3 Ways to parse JSON String inwards Java? (tutorial)
• How to purpose Google Protocol Buffer inwards Java? (tutorial)
• How to purpose Gson to convert JSON to Java Object? (example)

P.S. - If yous are looking for online grooming to larn how to develop RESTful Web Services inwards Java using Spring framework, I advise yous joining Eugen Paraschiv's REST alongside Spring course. The class has diverse options depending on your sense degree too how much yous desire to larn e.g. beginner's class, intermediate class, too original class. You tin laissez passer notice bring together the i which suits yous better, though I advise joining the masterclass if yous are serious most becoming an practiced Java REST developer.

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