Package com.inductiveautomation.ignition.common

Class JsonUtilities

java.lang.Object

com.inductiveautomation.ignition.common.JsonUtilities

public class JsonUtilities
extends java.lang.Object

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	JsonUtilities.ByteArrayAdapter	Encodes byte[] objects as Base64

Constructor Summary

Constructors

Constructor	Description
JsonUtilities()

Method Summary

Modifier and Type	Method	Description
static <T> java.util.List<T>	arrayMap(com.inductiveautomation.ignition.common.gson.JsonArray array, java.util.function.Function<com.inductiveautomation.ignition.common.gson.JsonElement,T> mapper)	Converts a json array into a java list of objects, mapping each element to the type desired.
static com.inductiveautomation.ignition.common.gson.JsonObject	asJsonObject(java.lang.Object... pairs)	Convenience function for making simple name-value pair objects.
static com.inductiveautomation.ignition.common.gson.JsonElement	createDeterministicCopy(com.inductiveautomation.ignition.common.gson.JsonElement json)	Like a JsonElement.deepCopy, except sorts the keys of each JsonObject first.
static com.inductiveautomation.ignition.common.gson.JsonObject	createFilteredCopy(com.inductiveautomation.ignition.common.gson.JsonObject root, java.util.function.Predicate<JsonPath> pass)	Creates a deep copy of the json object omitting any portions that don't pass the predicate.
static com.inductiveautomation.ignition.common.gson.JsonElement	javaToJson(java.lang.Object value)	Attempts to parse a java object into a JsonElement.
static java.lang.Object	json2Java(com.inductiveautomation.ignition.common.gson.JsonElement element)	Converts from a json tree to the canonical java object representation.
static com.inductiveautomation.ignition.common.gson.JsonObject	merge(com.inductiveautomation.ignition.common.gson.JsonObject... jsonObjects)	Merge any number of JsonObjects.
static com.inductiveautomation.ignition.common.gson.JsonPrimitive	primitive(java.lang.Object value)
static java.util.Optional<com.inductiveautomation.ignition.common.gson.JsonElement>	read(com.inductiveautomation.ignition.common.gson.JsonElement json, java.lang.String path)
static java.util.Optional<com.inductiveautomation.ignition.common.gson.JsonArray>	readArray(com.inductiveautomation.ignition.common.gson.JsonElement json, java.lang.String path)
static boolean	readBoolean(com.inductiveautomation.ignition.common.gson.JsonElement json, java.lang.String path, boolean defaultValue)
static int	readInteger(com.inductiveautomation.ignition.common.gson.JsonElement json, java.lang.String path, int defaultValue)	Attempts to read an integer value from a json structure.
static long	readLong(com.inductiveautomation.ignition.common.gson.JsonElement json, java.lang.String path, long defaultValue)
static double	readNumber(com.inductiveautomation.ignition.common.gson.JsonElement json, java.lang.String path, double defaultValue)	Attempts to read a double value from a json structure.
static java.util.Optional<com.inductiveautomation.ignition.common.gson.JsonObject>	readObject(com.inductiveautomation.ignition.common.gson.JsonElement json, java.lang.String path)
static short	readShort(com.inductiveautomation.ignition.common.gson.JsonElement json, java.lang.String path, short defaultValue)
static java.lang.String	readString(com.inductiveautomation.ignition.common.gson.JsonElement json, java.lang.String path, java.lang.String defaultValue)	Attempts to read a string value from a json structure.
static void	write(DocumentElement element, JsonPath jsonPath, java.lang.Object value, boolean allowNewMembers)	Writes the given value to the location in the document described by the jsonPath.
static void	write(com.inductiveautomation.ignition.common.gson.JsonElement element, JsonPath jsonPath, java.lang.Object value, boolean allowNewMembers)	Writes the given value to the location in the document described by the jsonPath.

Methods inherited from class java.lang.Object

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

Constructor Detail

JsonUtilities

public JsonUtilities()

Method Detail

asJsonObject

public static com.inductiveautomation.ignition.common.gson.JsonObject asJsonObject(java.lang.Object... pairs)

Convenience function for making simple name-value pair objects.

readString

public static java.lang.String readString(@Nullable
                                          com.inductiveautomation.ignition.common.gson.JsonElement json,
                                          @Nonnull
                                          java.lang.String path,
                                          @Nullable
                                          java.lang.String defaultValue)

Attempts to read a string value from a json structure. Extremely lenient. If anything isn't there along the path (including if the entire json structure is null), then the provided default value will be used instead.

Parameters:

json - The json structure to search through.

path - A path to what you're trying to read. Will be parsed with JsonPath.parse(String), and will throw an IllegalArgumentException if the path is malformed

defaultValue - The value to use if anything isn't where it should be.

readNumber

public static double readNumber(@Nullable
                                com.inductiveautomation.ignition.common.gson.JsonElement json,
                                @Nonnull
                                java.lang.String path,
                                double defaultValue)

Attempts to read a double value from a json structure. Extremely lenient. If anything isn't there along the path (including if the entire json structure is null), then the provided default value will be used instead.

Parameters:

json - The json structure to search through.

path - A path to what you're trying to read. Will be parsed with JsonPath.parse(String), and will throw an IllegalArgumentException if the path is malformed

defaultValue - The value to use if anything isn't where it should be.

readInteger

public static int readInteger(@Nullable
                              com.inductiveautomation.ignition.common.gson.JsonElement json,
                              @Nonnull
                              java.lang.String path,
                              int defaultValue)

Attempts to read an integer value from a json structure. Extremely lenient. If anything isn't there along the path (including if the entire json structure is null), then the provided default value will be used instead.

Parameters:

json - The json structure to search through.

path - A path to what you're trying to read. Will be parsed with JsonPath.parse(String), and will throw an IllegalArgumentException if the path is malformed

defaultValue - The value to use if anything isn't where it should be.

readShort

public static short readShort(@Nullable
                              com.inductiveautomation.ignition.common.gson.JsonElement json,
                              @Nonnull
                              java.lang.String path,
                              short defaultValue)

readLong

public static long readLong(@Nullable
                            com.inductiveautomation.ignition.common.gson.JsonElement json,
                            @Nonnull
                            java.lang.String path,
                            long defaultValue)

readBoolean

public static boolean readBoolean(@Nullable
                                  com.inductiveautomation.ignition.common.gson.JsonElement json,
                                  @Nonnull
                                  java.lang.String path,
                                  boolean defaultValue)

readObject

public static java.util.Optional<com.inductiveautomation.ignition.common.gson.JsonObject> readObject(com.inductiveautomation.ignition.common.gson.JsonElement json,
                                                                                                     java.lang.String path)

readArray

public static java.util.Optional<com.inductiveautomation.ignition.common.gson.JsonArray> readArray(com.inductiveautomation.ignition.common.gson.JsonElement json,
                                                                                                   java.lang.String path)

read

public static java.util.Optional<com.inductiveautomation.ignition.common.gson.JsonElement> read(com.inductiveautomation.ignition.common.gson.JsonElement json,
                                                                                                java.lang.String path)

merge

public static com.inductiveautomation.ignition.common.gson.JsonObject merge(com.inductiveautomation.ignition.common.gson.JsonObject... jsonObjects)

Merge any number of JsonObjects. Similar to Object.assign in the web world: the properties of object n + 1 will overwrite the properties of object n where n refers to the index of the nth var arg.

Parameters:

jsonObjects - The JsonObjects to merge. If it is null, this method will return null. If any one of the arguments is null, it will be skipped in the merging process.

Returns:

The merged JsonObject or null if the input was null.

createDeterministicCopy

public static com.inductiveautomation.ignition.common.gson.JsonElement createDeterministicCopy(com.inductiveautomation.ignition.common.gson.JsonElement json)

Like a JsonElement.deepCopy, except sorts the keys of each JsonObject first.

createFilteredCopy

public static com.inductiveautomation.ignition.common.gson.JsonObject createFilteredCopy(com.inductiveautomation.ignition.common.gson.JsonObject root,
                                                                                         java.util.function.Predicate<JsonPath> pass)

Creates a deep copy of the json object omitting any portions that don't pass the predicate. Any array elements that don't pass the predicate will be replaced with nulls so that arrays stay the same size.

write

public static void write(com.inductiveautomation.ignition.common.gson.JsonElement element,
                         JsonPath jsonPath,
                         java.lang.Object value,
                         boolean allowNewMembers)
                  throws java.lang.IllegalArgumentException

Writes the given value to the location in the document described by the jsonPath.

Parameters:

element - the document (or array, etc) to write to.

jsonPath - the path to the target element.

value - the value to write.

allowNewMembers - if false, will require that the entire path be located for write. If true and the last element of the jsonPath doesn't exist, and the penultimate element is an array or an object, a new member will be created.

Throws:

java.lang.IllegalArgumentException - thrown if the path cannot be found, or if it is not a valid write target.

write

public static void write(DocumentElement element,
                         JsonPath jsonPath,
                         java.lang.Object value,
                         boolean allowNewMembers)
                  throws java.lang.IllegalArgumentException

Writes the given value to the location in the document described by the jsonPath.

Parameters:

element - the document (or array, etc) to write to.

jsonPath - the path to the target element.

value - the value to write.

allowNewMembers - if false, will require that the entire path be located for write. If true and the last element of the jsonPath doesn't exist, and the penultimate element is an array or an object, a new member will be created.

Throws:

java.lang.IllegalArgumentException - thrown if the path cannot be found, or if it is not a valid write target.

json2Java

public static java.lang.Object json2Java(com.inductiveautomation.ignition.common.gson.JsonElement element)

Converts from a json tree to the canonical java object representation. For example, a JsonPrimitive representing a string, becomes a java String. An array becomes a List, an object becomes a HashMap, etc.

javaToJson

public static com.inductiveautomation.ignition.common.gson.JsonElement javaToJson(java.lang.Object value)

Attempts to parse a java object into a JsonElement.

primitive

public static com.inductiveautomation.ignition.common.gson.JsonPrimitive primitive(java.lang.Object value)

arrayMap

@Nonnull
public static <T> java.util.List<T> arrayMap(@Nonnull
                                             com.inductiveautomation.ignition.common.gson.JsonArray array,
                                             @Nonnull
                                             java.util.function.Function<com.inductiveautomation.ignition.common.gson.JsonElement,T> mapper)

Converts a json array into a java list of objects, mapping each element to the type desired.