Package org.kiwiproject.json

Class JsonHelper

java.lang.Object
org.kiwiproject.json.JsonHelper
public class JsonHelper extends Object
A bunch of utilities to make it easier to work with JSON.

One specific note on methods that accept paths. The syntax used to indicate array paths consists of the array property name, followed by a period, followed by the array index in square brackets. For example, if to find the first value in an array property luckyNumbers, the path is luckyNumbers.[0]. Similarly, to find the 13th lucky number the path is luckyNumbers.[12].

Paths for nested JSON objects follow the syntax objectName.propertyName; for JSON that contains a homeAddress object that contains a zipCode, the path is homeAddress.zipCode.

Implementation Note:
This uses Jackson to perform JSON mapping to and from objects, so Jackson will need to be available at runtime. In addition, if you use the no-args constructor, this relies on Dropwizard's Jackson class which does a bunch of configuration on the default Jackson ObjectMapper. So you would also need Dropwizard available at runtime as well, specifically dropwizard-jackson.

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    static enum 
    JsonHelper.MergeOption
    Describes how objects are to be merged.
    static enum 
    JsonHelper.OutputFormat
    Represents an output format when serializing an object to JSON.

  • Constructor Summary

    Constructors
    Constructor
    Description
    JsonHelper()
    Create a new instance using an ObjectMapper created using newDropwizardObjectMapper().
    JsonHelper(com.fasterxml.jackson.databind.ObjectMapper objectMapper)
    Create a new instance using the given ObjectMapper.

  • Method Summary

    Modifier and Type
    Method
    Description
    static com.fasterxml.jackson.databind.ObjectMapper
    configureForMillisecondDateTimestamps(com.fasterxml.jackson.databind.ObjectMapper mapper)
    Configure the given ObjectMapper to read and write timestamps as milliseconds.
    <T> T
    convert(Object fromObject, com.fasterxml.jackson.core.type.TypeReference<T> targetType)
    Converts the given object to an object of the target type described by the TypeReference.
    <T> T
    convert(Object fromObject, Class<T> targetType)
    Converts the given object to an object of the target type.
    Map<String,Object>
    convertToMap(Object fromObject)
    Converts the given object to a map with String keys and Object values.
    <K, V> Map<K,V>
    convertToMap(Object fromObject, com.fasterxml.jackson.core.type.TypeReference<Map<K,V>> targetMapType)
    Converts the given object to a map using the given TypeReference.
    <T> T
    copy(T object)
    Copies the given object by converting to JSON and then converting the JSON back to an object of the same class as the copied object.
    <T, R> R
    copy(T object, Class<R> targetClass)
    Copies the given object by converting to JSON and then converting the JSON back to an object of the given target class.
    <T, R> R
    copyIgnoringPaths(T object, Class<R> targetClass, String... ignoredPaths)
    Copies the given object by converting to JSON, ignoring the given paths, and then converting the JSON back to an object of the given target class.
    JsonDetectionResult
    detectJson(@Nullable String content)
    Use Jackson's data format detection to determine if the given content is JSON, assuming UTF-8 as the charset.
    JsonDetectionResult
    detectJson(@Nullable String content, Charset charset)
    Use Jackson's data format detection to determine if the given content is JSON.
    com.fasterxml.jackson.databind.ObjectMapper
    getObjectMapper()
    Provides direct access to the underlying object mapper.
    <T> T
    getPath(Object object, String path, com.fasterxml.jackson.core.type.TypeReference<T> targetType)
    Get the value at the given path in the object, with the type as the given target class.
    <T> T
    getPath(Object object, String path, Class<T> targetClass)
    Get the value at the given path in the object, with the type as the given target class.
    <T> T
    getPath(String json, String path, com.fasterxml.jackson.core.type.TypeReference<T> targetType)
    Get the value at the given path in the JSON, with the type as the given target class.
    <T> T
    getPath(String json, String path, Class<T> targetClass)
    Get the value at the given path in the JSON, with the type as the given target class.
    boolean
    isJson(@Nullable String content)
    Use Jackson's data format detection to determine if the given content is JSON, assuming UTF-8 as the charset.
    boolean
    isJson(@Nullable String content, Charset charset)
    Use Jackson's data format detection to determine if the given content is JSON.
    Map<String,List<String>>
    jsonDiff(@NonNull List<Object> objectList, String... ignoredPaths)
    Compare an object to an arbitrary number of other objects via their JSON differences.
    Map<String,List<String>>
    jsonDiff(@NonNull List<String> listOfJson)
    Compare a JSON object to an arbitrary number of other objects via their JSON differences.
    Map<String,List<String>>
    jsonDiff(@Nullable Object object1, @Nullable Object object2, String... ignoredPaths)
    Compare two objects via their JSON differences, optionally ignoring one or more paths.
    boolean
    jsonEquals(Object... objects)
    Compare the JSON representation of multiple objects.
    boolean
    jsonEqualsIgnoringPaths(Object object1, Object object2, String... ignoredPaths)
    Compare the JSON representations of two objects, optionally ignoring paths.
    <T> boolean
    jsonPathsEqual(Object object1, Object object2, String path, Class<T> targetClass)
    Compare the values at a given path in two objects.
    List<String>
    listObjectPaths(@Nullable Object object)
    Parse the given object as JSON, and return a list containing the property paths in the object.
    com.fasterxml.jackson.databind.JsonNode
    mergeNodes(com.fasterxml.jackson.databind.JsonNode destinationNode, com.fasterxml.jackson.databind.JsonNode updateNode, JsonHelper.MergeOption... mergeOptions)
    Updates (mutates) destinationNode with values from updateNode.
    <T> T
    mergeObjects(T originalObject, Object updateObject, JsonHelper.MergeOption... mergeOptions)
    Merge values in updateObject into the original object, using the given merge options.
    static JsonHelper
    newDropwizardJsonHelper()
    Create a new JsonHelper with an ObjectMapper supplied by newDropwizardObjectMapper().
    static com.fasterxml.jackson.databind.ObjectMapper
    newDropwizardObjectMapper()
    Creates a new ObjectMapper configured using the Dropwizard Jackson.newObjectMapper() factory method.
    com.fasterxml.jackson.databind.JsonNode
    removePath(@Nullable Object object, String path)
    Remove the given path from the object.
    Map<String,String>
    toFlatMap(@Nullable Object object)
    Parse the given object as JSON, then flatten all its properties to a map whose keys are the object property names and whose values are converted to Strings.
    <T> Map<String,T>
    toFlatMap(@Nullable Object object, Class<T> valueClass)
    Parse the given object as JSON, then flatten all its properties to a map whose keys are the object property names and whose values are converted to the given valueClass type.
    String
    toJson(@Nullable Object object)
    Convert the given object to JSON using the JsonHelper.OutputFormat.DEFAULT format.
    String
    toJson(@Nullable Object object, JsonHelper.OutputFormat format)
    Convert the given object to JSON using the given format.
    String
    toJson(@Nullable Object object, JsonHelper.OutputFormat format, @Nullable Class<?> jsonView)
    Convert the given object to JSON using the given format and optionally a class representing the JsonView to use.
    String
    toJsonFromKeyValuePairs(Object... kvPairs)
    Consider the given arguments as key/value pairs, and convert those pairs to a JSON representation.
    String
    toJsonIgnoringPaths(@Nullable Object object, String... ignoredPaths)
    Convert the given object to JSON, but ignoring (excluding) the given paths.
    Map<String,Object>
    toMap(@Nullable String json)
    Convert the given JSON into a map with String keys and Object values.
    <K, V> Map<K,V>
    toMap(@Nullable String json, com.fasterxml.jackson.core.type.TypeReference<Map<K,V>> targetMapType)
    Convert the given JSON into a map with keys of type K and values of type V.
    <T> T
    toObject(@Nullable String json, com.fasterxml.jackson.core.type.TypeReference<T> targetType)
    Convert the given JSON into an object of type T using the given TypeReference.
    <T> T
    toObject(@Nullable String json, Class<T> targetClass)
    Convert the given JSON into the specified type.
    <T> List<T>
    toObjectList(@Nullable String json, com.fasterxml.jackson.core.type.TypeReference<List<T>> targetListType)
    Convert the given JSON into a List of objects of type T.
    <T> Optional<T>
    toObjectOptional(@Nullable String json, Class<T> targetClass)
    Return an Optional that will contain an object of the expected type T, or an empty Optional if the input JSON is blank
    <T> T
    toObjectOrDefault(@Nullable String json, Class<T> clazz, T defaultValue)
    Convert the given JSON into the specified type, or return the given default value if input JSON is blank.
    <T> T
    toObjectOrSupply(@Nullable String json, Class<T> clazz, Supplier<T> defaultValueSupplier)
    Convert the given JSON into the specified type, or return the supplied default value if input JSON is blank.
    <T> T
    updatePath(@Nullable Object object, String path, Object value, Class<T> targetClass)
    Update the given path in the object with the new value, converting to the target class.

    Methods inherited from class java.lang.Object

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

  • Constructor Details

    • JsonHelper

      public JsonHelper()
      Create a new instance using an ObjectMapper created using newDropwizardObjectMapper().

    • JsonHelper

      public JsonHelper(com.fasterxml.jackson.databind.ObjectMapper objectMapper)
      Create a new instance using the given ObjectMapper.
      Parameters:
      objectMapper - the ObjectMapper to use

  • Method Details

    • newDropwizardJsonHelper

      public static JsonHelper newDropwizardJsonHelper()
      Create a new JsonHelper with an ObjectMapper supplied by newDropwizardObjectMapper().
      Returns:
      a new JsonHelper instance

    • newDropwizardObjectMapper

      public static com.fasterxml.jackson.databind.ObjectMapper newDropwizardObjectMapper()
      Creates a new ObjectMapper configured using the Dropwizard Jackson.newObjectMapper() factory method. It also configures the returned mapper to read and write timestamps as milliseconds.
      Returns:
      a new ObjectMapper
      See Also:

    • configureForMillisecondDateTimestamps

      public static com.fasterxml.jackson.databind.ObjectMapper configureForMillisecondDateTimestamps(com.fasterxml.jackson.databind.ObjectMapper mapper)
      Configure the given ObjectMapper to read and write timestamps as milliseconds.
      Parameters:
      mapper - the ObjectMapper to change
      Returns:
      the same instance, configured to write/read timestamps as milliseconds

    • getObjectMapper

      public com.fasterxml.jackson.databind.ObjectMapper getObjectMapper()
      Provides direct access to the underlying object mapper. Care should be taken when accessing the ObjectMapper directly, particularly if any changes are made to how objects are serialized/de-serialized.
      Returns:
      the object mapper; any changes made to it will potentially change the behavior of this JsonHelper instance

    • isJson

      public boolean isJson(@Nullable String content)
      Use Jackson's data format detection to determine if the given content is JSON, assuming UTF-8 as the charset.
      Parameters:
      content - the content to check
      Returns:
      true if detected as JSON, false otherwise (including if content is null or blank, or if an exception is thrown detecting the format)

    • isJson

      public boolean isJson(@Nullable String content, Charset charset)
      Use Jackson's data format detection to determine if the given content is JSON.
      Parameters:
      content - the content to check
      charset - the character set to use
      Returns:
      true if detected as JSON, false otherwise (including if content is null or blank, or if an exception is thrown detecting the format)
      See Also:
      • DataFormatDetector.findFormat(byte[])

    • detectJson

      public JsonDetectionResult detectJson(@Nullable String content)
      Use Jackson's data format detection to determine if the given content is JSON, assuming UTF-8 as the charset.
      Parameters:
      content - the content to check
      Returns:
      the detection result

    • detectJson

      public JsonDetectionResult detectJson(@Nullable String content, Charset charset)
      Use Jackson's data format detection to determine if the given content is JSON.
      Parameters:
      content - the content to check
      charset - the character set to use
      Returns:
      the detection result

    • toJson

      public String toJson(@Nullable Object object)
      Convert the given object to JSON using the JsonHelper.OutputFormat.DEFAULT format.
      Parameters:
      object - the object to convert
      Returns:
      a JSON representation of the given object, or null if the given object is null

    • toJson

      public String toJson(@Nullable Object object, JsonHelper.OutputFormat format)
      Convert the given object to JSON using the given format.
      Parameters:
      object - the object to convert
      format - the format to use
      Returns:
      a JSON representation of the given object, or null if the given object is null

    • toJson

      public String toJson(@Nullable Object object, JsonHelper.OutputFormat format, @Nullable Class<?> jsonView)
      Convert the given object to JSON using the given format and optionally a class representing the JsonView to use.
      Parameters:
      object - the object to convert
      format - the format to use
      jsonView - the nullable JsonView class
      Returns:
      a JSON representation of the given object, or null if the given object is null

    • toJsonFromKeyValuePairs

      public String toJsonFromKeyValuePairs(Object... kvPairs)
      Consider the given arguments as key/value pairs, and convert those pairs to a JSON representation.
      Parameters:
      kvPairs - the objects to treat as key/value pairs
      Returns:
      the JSON representation
      Throws:
      IllegalArgumentException - if an odd number of arguments is supplied

    • toJsonIgnoringPaths

      public String toJsonIgnoringPaths(@Nullable Object object, String... ignoredPaths)
      Convert the given object to JSON, but ignoring (excluding) the given paths.
      Parameters:
      object - the object to convert
      ignoredPaths - the paths to ignore/exclude
      Returns:
      the JSON representation without the ignored paths

    • toObject

      public <T> T toObject(@Nullable String json, Class<T> targetClass)
      Convert the given JSON into the specified type.
      Type Parameters:
      T - the object type
      Parameters:
      json - the JSON content
      targetClass - the type of object to convert into
      Returns:
      a new instance of the given type, or null if the given input JSON is blank

    • toObjectOrDefault

      public <T> T toObjectOrDefault(@Nullable String json, Class<T> clazz, T defaultValue)
      Convert the given JSON into the specified type, or return the given default value if input JSON is blank.
      Type Parameters:
      T - the object type
      Parameters:
      json - the JSON content
      clazz - the type of object to convert into
      defaultValue - the default value to use if necessary
      Returns:
      a new instance of the given type, or return defaultValue if the given input JSON is blank

    • toObjectOrSupply

      public <T> T toObjectOrSupply(@Nullable String json, Class<T> clazz, Supplier<T> defaultValueSupplier)
      Convert the given JSON into the specified type, or return the supplied default value if input JSON is blank.
      Type Parameters:
      T - the object type
      Parameters:
      json - the JSON content
      clazz - the type of object to convert into
      defaultValueSupplier - the default value Supplier to call if necessary
      Returns:
      a new instance of the given type, or return the value supplied by defaultValueSupplier if the given input JSON is blank

    • toObject

      public <T> T toObject(@Nullable String json, com.fasterxml.jackson.core.type.TypeReference<T> targetType)
      Convert the given JSON into an object of type T using the given TypeReference.
      Type Parameters:
      T - the object type
      Parameters:
      json - the JSON content
      targetType - the TypeReference representing the target object type
      Returns:
      a new instance of the type encapsulated by the TypeReference, or null if the input JSON is blank

    • toObjectOptional

      public <T> Optional<T> toObjectOptional(@Nullable String json, Class<T> targetClass)
      Return an Optional that will contain an object of the expected type T, or an empty Optional if the input JSON is blank
      Type Parameters:
      T - the object type
      Parameters:
      json - the JSON content
      targetClass - the type of object to convert into
      Returns:
      an Optional that may contain a converted object

    • toObjectList

      public <T> List<T> toObjectList(@Nullable String json, com.fasterxml.jackson.core.type.TypeReference<List<T>> targetListType)
      Convert the given JSON into a List of objects of type T.
      Type Parameters:
      T - the object type
      Parameters:
      json - the JSON content
      targetListType - the TypeReference representing the list target type
      Returns:
      a list containing objects of the given type, or null if the input is blank

    • toMap

      public Map<String,Object> toMap(@Nullable String json)
      Convert the given JSON into a map with String keys and Object values.
      Parameters:
      json - the JSON content
      Returns:
      the parsed map, or null if the input JSON is blank

    • toMap

      public <K, V> Map<K,V> toMap(@Nullable String json, com.fasterxml.jackson.core.type.TypeReference<Map<K,V>> targetMapType)
      Convert the given JSON into a map with keys of type K and values of type V.
      Type Parameters:
      K - the type of keys in the map
      V - the type of values in the map
      Parameters:
      json - the JSON content
      targetMapType - the TypeReference representing the target map type
      Returns:
      the parsed map, or null if the input JSON is blank

    • toFlatMap

      public Map<String,String> toFlatMap(@Nullable Object object)
      Parse the given object as JSON, then flatten all its properties to a map whose keys are the object property names and whose values are converted to Strings.

      For more details on the behavior, see toFlatMap(Object, Class).

      Parameters:
      object - the object to flatten
      Returns:
      a map with string keys and values converted to strings, or null if the given object is null

    • toFlatMap

      public <T> Map<String,T> toFlatMap(@Nullable Object object, Class<T> valueClass)
      Parse the given object as JSON, then flatten all its properties to a map whose keys are the object property names and whose values are converted to the given valueClass type. In practice, this will often just be Object.class but could be a more specific type, e.g. if you have a map containing student names and grades then the values could all be of type Double.

      This also flattens arrays/collections and maps. Flattened arrays use the following syntax: arrayPropertyName.[index]. For example, luckyNumbers.[0] is the first element in a collection named luckyNumbers. For maps, the syntax is: mapPropertyName.key. For example, emailAddresses.home contains the value in the emailAddresses map under the key home.

      Type Parameters:
      T - the generic type of the map values
      Parameters:
      object - the object to flatten
      valueClass - the target class for the map's values
      Returns:
      a map with string keys and values converted to the specified type, or null if the given object is null

    • copy

      public <T> T copy(T object)
      Copies the given object by converting to JSON and then converting the JSON back to an object of the same class as the copied object.
      Type Parameters:
      T - the type of object being copied
      Parameters:
      object - the object to copy
      Returns:
      the copied object of the target class

    • copy

      public <T, R> R copy(T object, Class<R> targetClass)
      Copies the given object by converting to JSON and then converting the JSON back to an object of the given target class.
      Type Parameters:
      T - the type of object being copied
      R - the type of object to copy into
      Parameters:
      object - the object to copy
      targetClass - the target class (it may be different from the original)
      Returns:
      the copied object of the target class

    • copyIgnoringPaths

      public <T, R> R copyIgnoringPaths(T object, Class<R> targetClass, String... ignoredPaths)
      Copies the given object by converting to JSON, ignoring the given paths, and then converting the JSON back to an object of the given target class.
      Type Parameters:
      T - the type of object being copied
      R - the type of object to copy into
      Parameters:
      object - the object to copy
      targetClass - the target class (it may be different from the original)
      ignoredPaths - the paths to ignore during the copy
      Returns:
      the copied object of the target class

    • convert

      public <T> T convert(Object fromObject, Class<T> targetType)
      Converts the given object to an object of the target type.
      Type Parameters:
      T - the target type
      Parameters:
      fromObject - the object to convert
      targetType - the type of object to convert to
      Returns:
      a new instance of the target type
      See Also:
      • ObjectMapper.convertValue(Object, Class)

    • convert

      public <T> T convert(Object fromObject, com.fasterxml.jackson.core.type.TypeReference<T> targetType)
      Converts the given object to an object of the target type described by the TypeReference.
      Type Parameters:
      T - the target type
      Parameters:
      fromObject - the object to convert
      targetType - a TypeReference that describes the target type
      Returns:
      a new instance of the target type
      See Also:
      • ObjectMapper.convertValue(Object, TypeReference)

    • convertToMap

      public Map<String,Object> convertToMap(Object fromObject)
      Converts the given object to a map with String keys and Object values.
      Parameters:
      fromObject - the object to convert
      Returns:
      a new map instance

    • convertToMap

      public <K, V> Map<K,V> convertToMap(Object fromObject, com.fasterxml.jackson.core.type.TypeReference<Map<K,V>> targetMapType)
      Converts the given object to a map using the given TypeReference.

      Unless you have specialized requirements, usually convertToMap(Object) will be what you want.

      Type Parameters:
      K - the type of keys in the map
      V - the type of values in the map
      Parameters:
      fromObject - the object to convert
      targetMapType - the TypeReference describing the target map type
      Returns:
      a new map instance

    • getPath

      public <T> T getPath(Object object, String path, Class<T> targetClass)
      Get the value at the given path in the object, with the type as the given target class.
      Type Parameters:
      T - the return type
      Parameters:
      object - the object to search
      path - the path within the object (e.g. "homeAddress.zipCode")
      targetClass - the type associated with the given path
      Returns:
      an instance of the specified target class

    • getPath

      public <T> T getPath(String json, String path, Class<T> targetClass)
      Get the value at the given path in the JSON, with the type as the given target class.
      Type Parameters:
      T - the return type
      Parameters:
      json - the JSON to search
      path - the path within the object (e.g. "homeAddress.zipCode")
      targetClass - the type associated with the given path
      Returns:
      an instance of the specified target class

    • getPath

      public <T> T getPath(Object object, String path, com.fasterxml.jackson.core.type.TypeReference<T> targetType)
      Get the value at the given path in the object, with the type as the given target class.
      Type Parameters:
      T - the return type
      Parameters:
      object - the object to search
      path - the path within the object (e.g. "homeAddress.zipCode")
      targetType - the type associated with the given path
      Returns:
      an instance of the specified target class

    • getPath

      public <T> T getPath(String json, String path, com.fasterxml.jackson.core.type.TypeReference<T> targetType)
      Get the value at the given path in the JSON, with the type as the given target class.
      Type Parameters:
      T - the return type
      Parameters:
      json - the JSON to search
      path - the path within the object (e.g. "homeAddress.zipCode")
      targetType - the type associated with the given path
      Returns:
      an instance of the specified target class

    • removePath

      public com.fasterxml.jackson.databind.JsonNode removePath(@Nullable Object object, String path)
      Remove the given path from the object.
      Parameters:
      object - the object from which to remove a path
      path - the path to remove
      Returns:
      a JsonNode with the given path removed

    • updatePath

      public <T> T updatePath(@Nullable Object object, String path, Object value, Class<T> targetClass)
      Update the given path in the object with the new value, converting to the target class.
      Type Parameters:
      T - the type of the input object
      Parameters:
      object - the original object
      path - the path to update
      value - the new value to use
      targetClass - the type of object to return
      Returns:
      a new instance of the given target type

    • jsonDiff

      public Map<String,List<String>> jsonDiff(@Nullable Object object1, @Nullable Object object2, String... ignoredPaths)
      Compare two objects via their JSON differences, optionally ignoring one or more paths. The diff is from the perspective of the first object.

      The returned map of differences has keys that are the properties that are different. The map values are the values for the corresponding key/property in the first and second objects, respectively.

      NOTE: This is an expensive operation so be careful of using it in production code in areas where performance is critical.

      Parameters:
      object1 - the first object
      object2 - the second object
      ignoredPaths - the paths to ignore in the comparison
      Returns:
      a map containing a list of differences

    • jsonDiff

      public Map<String,List<String>> jsonDiff(@NonNull List<Object> objectList, String... ignoredPaths)
      Compare an object to an arbitrary number of other objects via their JSON differences. The diff is from the perspective of the first object in the given list.

      The returned map of differences has keys that are the properties that are different. The map values are the values for the corresponding key/property in the first and subsequent objects, respectively.

      NOTE: This is an expensive operation so be careful of using it in production code in areas where performance is critical.

      Parameters:
      objectList - the list of objects to compare; the first object is the reference object
      ignoredPaths - the paths to ignore in the comparison
      Returns:
      a map containing a list of differences

    • jsonDiff

      public Map<String,List<String>> jsonDiff(@NonNull List<String> listOfJson)
      Compare a JSON object to an arbitrary number of other objects via their JSON differences. The diff is from the perspective of the first JSON object in the given list.

      The returned map of differences has keys that are the properties that are different. The map values are the values for the corresponding key/property in the first and subsequent objects, respectively.

      NOTE: This is an expensive operation so be careful of using it in production code in areas where performance is critical.

      Parameters:
      listOfJson - the list of JSON objects to compare
      Returns:
      map containing a list of differences

    • jsonEquals

      public boolean jsonEquals(Object... objects)
      Compare the JSON representation of multiple objects.
      Parameters:
      objects - the objects to compare
      Returns:
      true if all the given objects have equal JSON representations

    • jsonEqualsIgnoringPaths

      public boolean jsonEqualsIgnoringPaths(Object object1, Object object2, String... ignoredPaths)
      Compare the JSON representations of two objects, optionally ignoring paths.
      Parameters:
      object1 - the first object to compare
      object2 - the second object to compare
      ignoredPaths - the paths to ignore in the comparison
      Returns:
      true if the objects have equal JSON representations, ignoring the given paths

    • jsonPathsEqual

      public <T> boolean jsonPathsEqual(Object object1, Object object2, String path, Class<T> targetClass)
      Compare the values at a given path in two objects.
      Type Parameters:
      T - the object type for the given path
      Parameters:
      object1 - the first object
      object2 - the second object
      path - the path to compare
      targetClass - the type of object at the given path
      Returns:
      true if the two objects have an equal value at the given path; the two values are compared using Objects.equals(Object, Object)

    • mergeObjects

      public <T> T mergeObjects(T originalObject, Object updateObject, JsonHelper.MergeOption... mergeOptions)
      Merge values in updateObject into the original object, using the given merge options.

      Note that the originalObject is not mutated in any way; it simply represents the original state to be updated with values from updateObject. Both originalObject and updateObject are converted to JSON before merging.

      Type Parameters:
      T - the type of the merged object
      Parameters:
      originalObject - the object into which updates will be merged (only used to read original state)
      updateObject - the object containing updates
      mergeOptions - zero or more JsonHelper.MergeOption
      Returns:
      a new instance of type T
      See Also:

    • mergeNodes

      public com.fasterxml.jackson.databind.JsonNode mergeNodes(com.fasterxml.jackson.databind.JsonNode destinationNode, com.fasterxml.jackson.databind.JsonNode updateNode, JsonHelper.MergeOption... mergeOptions)
      Updates (mutates) destinationNode with values from updateNode.
      Parameters:
      destinationNode - the node that will be updated (mutated)
      updateNode - the node containing updated values
      mergeOptions - zero or more JsonHelper.MergeOption
      Returns:
      the mutated destinationNode
      See Also:

    • listObjectPaths

      public List<String> listObjectPaths(@Nullable Object object)
      Parse the given object as JSON, and return a list containing the property paths in the object. The paths include arrays, collections and maps.

      For details on the property path syntax, see toFlatMap(Object, Class).

      Parameters:
      object - the object to list paths for
      Returns:
      a list of the property paths