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- Java - Renaming Files/Directories
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Groovy Synchronization
- groovy - Synchronization
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- Groovy - XML
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- Groovy - Parsing XML
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- Groovy - Simplified Notation
- Groovy - Closure based Querying
- Groovy - Closure based Creation
- Groovy - JSON
- Groovy - JSON
- Groovy - Parsing JSON
- Groovy - Creating JSON using JsonOutput
- Groovy - Creating JSON using JsonBuilder
- Groovy - Modifying JSON
- Groovy - Error Handling
- Groovy - Handling JSON Arrays
- Groovy - JSON Array Operations
- Groovy - JSON Objects
- Groovy - JSON Object Operations
- Groovy - Generics
- Groovy - Generics
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Groovy - Handling JSON Objects
In groovy, we can handle JSON objects easily using JsonSlurper. Whenever a JSON object is encountered as enclosed in curly braces, {}, JsonSlurper converts it into a Map instance. The keys and values of JSON objects are mapped to key-value pairs in the Map. In this chapter, we'll demonstrating scenarios of handling JSON objects using JsonSlurper and JsonBuilder.
Parsing JSON Object using JsonSlurper
Example.groovy
import groovy.json.JsonSlurper def jsonObjectText = ''' { "name": "Julie", "age": 32, "id": 1, "isManager": false, "courses" : ["java", "python"] }, ''' def slurper = new JsonSlurper() def employee = slurper.parseText(jsonObjectText) // prints groovy.json.internal.LazyMap println employee.getClass().name // prints the map println employee
Output
When we run the above program, we will get the following result.
groovy.json.internal.LazyMap [age:32, courses:[java, python], id:1, isManager:false, name:Julie]
Here we can see that JSON object is converted to a Map.
Parsing Nested JSON Objects using JsonSlurper
We can parse nested JSON objects as well. JsonSlurper automatically converts them into nested m as shown below −
Example.groovy
import groovy.json.JsonSlurper def nestedMapJsonString = ''' { "name": "Alice", "age": 28, "city": "Seattle", "address": { "street": "789 Pine Ln", "zip": "10115" }, "dept": "Admin" } ''' def jsonSlurper = new JsonSlurper() def nestedData = jsonSlurper.parseText(nestedMapJsonString) // prints 10155 println nestedData.address.zip
Output
When we run the above program, we will get the following result.
10155
Creating JSON Object using JsonBuilder
We can create JSON Objects easliy using JsonBuilder. Object structures can be defined using closures as shown in example below −
Example.groovy
import groovy.json.JsonBuilder import groovy.json.JsonOutput def employee = [ name: 'Julie', age: 32, id: 1 ] def builder = new JsonBuilder() builder { name employee.name age employee.age id employee.id department "Admin" } def jsonOutput = JsonOutput.prettyPrint(builder.toString()) println jsonOutput
Output
When we run the above program, we will get the following result.
{ "name": "Julie", "age": 32, "id": 1, "department": "Admin" }