gettingStarted.md

Getting Started

1 Add Jolt maven dependencies to your pom file

Maven Dependency to Add to your pom file

<dependency>
    <groupId>com.bazaarvoice.jolt</groupId>
    <artifactId>jolt-core</artifactId>
    <version>${latest.jolt.version}</version>
</dependency>
<dependency>
    <groupId>com.bazaarvoice.jolt</groupId>
    <artifactId>json-utils</artifactId>
    <version>${latest.jolt.version}</version>
</dependency>

Where latest.jolt.version looks like 0.0.16, and can be found by looking at the project's releases.

The two maven artifacts are:

1. jolt-core : only one dependency on apache.commons for StringUtils
   • The goal is for the jolt-core artifact to be pure Java, so that it does not cause any dependency issues.
2. json-utils : Jackson wrapper and testing utilities. Used by jolt-core as a test dependency.
   • If you are willing to pull in Jackson 2, this artifact provides nice utility methods.

2 Code and Sample Data

1. Copy-paste this code and sample data.
2. Get it to run
3. Replace the input and spec file with your own

JoltSample.java

Available here.

package com.bazaarvoice.jolt.sample;

import com.bazaarvoice.jolt.Chainr;
import com.bazaarvoice.jolt.JsonUtils;

import java.io.IOException;
import java.util.List;

public class JoltSample {

    public static void main(String[] args) throws IOException {

        // How to access the test artifacts, i.e. JSON files
        //  JsonUtils.classpathToList : assumes you put the test artifacts in your class path
        //  JsonUtils.filepathToList : you can use an absolute path to specify the files

        List chainrSpecJSON = JsonUtils.classpathToList( "/json/sample/spec.json" );
        Chainr chainr = Chainr.fromSpec( chainrSpecJSON );

        Object inputJSON = JsonUtils.classpathToObject( "/json/sample/input.json" );

        Object transformedOutput = chainr.transform( inputJSON );
        System.out.println( JsonUtils.toJsonString( transformedOutput ) );
    }
}

/json/sample/input.json

Available here.

{
    "rating": {
        "primary": {
            "value": 3
        },
        "quality": {
            "value": 3
        }
    }
}

/json/sample/spec.json

Available here.

[
    {
        "operation": "shift",
        "spec": {
            "rating": {
                "primary": {
                    "value": "Rating"
                },
                "*": {
                    "value": "SecondaryRatings.&1.Value",
                    "$": "SecondaryRatings.&.Id"
                }
            }
        }
    },
    {
        "operation": "default",
        "spec": {
            "Range" : 5,
            "SecondaryRatings" : {
                "*" : {
                    "Range" : 5
                }
            }
        }
    }
]

Output

With pretty formatting, looks like:

{
    "Rating": 3,
    "Range": 5,
    "SecondaryRatings": {
        "quality": {
            "Id": "quality",
            "Value": 3,
            "Range": 5
        }
    }
}