io.cdap.functions

Class JSON

java.lang.Object

io.cdap.functions.JSON

public final class JSON
extends Object

Collection of useful expression functions made available in the context of an expression. set-column column

Field Summary

Fields

Modifier and Type	Field and Description
static com.jayway.jsonpath.Configuration	GSON_CONFIGURATION

Constructor Summary

Constructors

Constructor and Description
JSON()

Method Summary

Modifier and Type	Method and Description
static com.google.gson.JsonElement	drop(com.google.gson.JsonElement element, String field, String... fields) Removes fields from a JSON inline.
static com.google.gson.JsonElement	drop(String json, String field, String... fields)
static String	join(com.google.gson.JsonElement element, String separator)
static com.google.gson.JsonElement	keysToLower(com.google.gson.JsonElement element) This function lowers the keys of the json.
static com.google.gson.JsonElement	parse(String json) Parses a column or string to JSON.
static com.google.gson.JsonElement	parse(String json, boolean toLower) Parses a column or string to JSON.
static com.google.gson.JsonElement	select(com.google.gson.JsonElement element, boolean toLower, String path, String... paths)
static com.google.gson.JsonElement	select(com.google.gson.JsonElement element, String path, String... paths)
static com.google.gson.JsonElement	select(String json, boolean toLower, String path, String... paths)
static com.google.gson.JsonElement	select(String json, String path, String... paths)
static String	stringify(com.google.gson.JsonElement element) This method converts a JavaScript value to a JSON string.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

GSON_CONFIGURATION

public static final com.jayway.jsonpath.Configuration GSON_CONFIGURATION

Constructor Detail

JSON

public JSON()

Method Detail

select

public static com.google.gson.JsonElement select(String json,
                                                 String path,
                                                 String... paths)

select

public static com.google.gson.JsonElement select(String json,
                                                 boolean toLower,
                                                 String path,
                                                 String... paths)

select

public static com.google.gson.JsonElement select(com.google.gson.JsonElement element,
                                                 String path,
                                                 String... paths)

select

public static com.google.gson.JsonElement select(com.google.gson.JsonElement element,
                                                 boolean toLower,
                                                 String path,
                                                 String... paths)

drop

public static com.google.gson.JsonElement drop(String json,
                                               String field,
                                               String... fields)

drop

public static com.google.gson.JsonElement drop(com.google.gson.JsonElement element,
                                               String field,
                                               String... fields)

Removes fields from a JSON inline. This method recursively iterates through the Json to delete one or more fields specified. It requires the Json to be parsed.

Parameters:

element - Json element to be parsed.

field - first field to be deleted.

fields - list of fields to be deleted.

Returns:

keysToLower

public static com.google.gson.JsonElement keysToLower(com.google.gson.JsonElement element)

This function lowers the keys of the json. it applies this transformation recurively.

Parameters:

element - to be transformed.

Returns:

modified element.

join

public static String join(com.google.gson.JsonElement element,
                          String separator)

stringify

public static String stringify(com.google.gson.JsonElement element)

This method converts a JavaScript value to a JSON string.

Parameters:

element - the value to convert to JSON string

Returns:

a JSON string.

parse

public static com.google.gson.JsonElement parse(String json)

Parses a column or string to JSON. This is equivalent to JSON.parse() This function by default lowercases the keys.

Parameters:

json - string representation of json.

Returns:

parsed json else throws an exception.

parse

public static com.google.gson.JsonElement parse(String json,
                                                boolean toLower)

Parses a column or string to JSON. This is equivalent to JSON.parse()

Parameters:

json - string representation of json.

toLower - true to lower case keys, false to leave it as-is.

Returns:

parsed json else throws an exception.