Package Torello.JSON

Class RJArrIntoConsumer

  • public class RJArrIntoConsumer
extends java.lang.Object
    RJArrIntoConsumer 🠞
    • RJArr - Read JsonArray
      This class is used for reading data directly from an already parsed JsonArray instance.

    • Into - Data that is extracted, is sent to a specific User-Provided Destination.

    • Consumer - Data is sent to a Java-Consumer.
    Utilities for parsing Json Array's and sending the parsed values into a Java Consumer Functional-Interface.

    This class builds on the J2EE Standard 'Glass-Fish' JSON Processor


    There are several JSON Parsers available, and even more implementations for serializing and de-serializing data to/from JSON. The Glass Fish Tool is included in the J2EE, and is available on GitHub. That is the one used by the Java HTML JAR Library (See: javax.json.* )

    Primary Classes Used: JsonArray and JsonObject

    This comment-note is intentionally repeated, verbatim, at the top of all Json Reader Classes in this package.


    JSON to Java Binding:
    JSON-Binding is the art of converting data that has been stored, saved or transmitted using Java-Script Object Notation into a Java Primitive or Object-Type. JSON can arrive into Java-Program Memory from almost any source. If you are wondering why such a massive amount of "work" is necessary just to convert a Json Integer into Java Integer, the value added is the extraordinary amount of attention paid to user configuration, error checking, & exception messaging. Methods here don't require more than 1 or 2 lines of code, and guarantee that a thorough type checking is performed.

    Unlike Java-Types which are checked by the Java-Compiler each-and-every time a programmer compiles his project, any guarantee that JSON-Type Data is pristine, uncorrupted, and in any kind of pre-agreed format may or may not be assured. The methods here are able to handle changes that might be made to an API (possibly from great distances away, and without the Software-Manager's consent). If an error could occur, configuration flags can be used to determine default error-recovery behaviors. If an exception does throw, the exception messages printed will contain multiple lines of detailed information.

    • Utilizes the Java-Standard javax.json.* Package-Library, & its Glass-Fish Implementation
    • Handles the Transfer & Conversion of All Json-Type's into Java-Type's with just One Line of Code
    • Provides all manner of User-Configurable Exception-Handling & Error-Decision Management via Class JFlag
    • Provides a Fine-Grained Suite of Exception-Classes, all with Consistent & Meaningful Error-Messages. Json Files can occasionally grow extremely large, and error messaging details make debugging easier
    • Primary Helper-Classes for the (Experimental) Google-Chrome Browser Automation Package

    The goal of Torello.JSON is to provide small, static helper methods in the same spirit as java.util.Objects and java.util.Arrays: simple calls that keep JSON handling out of your application logic. Instead of repeating loops, type checks, null checks, and exception wiring at every call site, these methods centralize that work behind a consistent set of straight-forward “read value” operations.


    Retrieve String, Object & Json-Types from a JsonArray; Send to a Consumer

    Each of the methods in this class, all declared 'static', accept a standard JsonArray as input, and will attempt to convert each of the elements of that array into the following output types. The provided table below explains which types are expected to be provided to the methods in this class, and what types will be sent to the User-Provided Consumer's after parsing and extracting the array elements.
    Array Element Type Returned / Emitted Type
    JsonObject Instance of User-Specified, Parameterized-Type <T>
    JsonString Instance of java.lang.String
    JsonObject -- same / no change --
    JsonArray -- same / no change --

    Each of the emitted types for these methods may be sent to one of two "kinds" of Java Consumer's. The JDK Standard Consumer, whose full package name is java.util.function.Consumer accepts the post-processed output from the arrays that are passed to these methodss. This consumer impements a Function-Interface with one method that accepts the type in the method signature.

    The second "kind" of Consumer which is available is provided by the Java-HTML '.jar' Library. It is known, simply, as an: IntIntTConsumer. Both of these User-Provided Consumers will accept post-processed array-entries, one by one, until the end of the array has been reached.
    Consumer Kind / Type Explanation of Use
    java.util.function.Consumer As elements are retrieved, extracted and processed from the User-Provided JsonArray, the are sent to the single-input parameter Lambda-Method that user has provided.
    IntIntTConsumer As elements are retrieved, they are passed to this Java-HTML Consumer, along with two primitive integers.

    The first 'int' is the array index of the JsonArray in which the item was located.

    The second 'int' is the "success count" for how many elements have been extracted from the array. Often these integers are identical, but in cases where the user has requested to skip on failure, the integers may differ.



    POJO De-Serialization:
    The methods that appear to de-serialize a JSON-Object into a standard Java-Object do not automatically generate a Java-Type based solely on the properties present within a JsonObject. Automatic type-creation (as exists in libraries such as 'Lombok') is not a feature offered by this package. These methods can reduce quite a bit of the work needed to convert Json into Java by offering methods which extact JsonValue's using just a single line of code.

    The methods in this class which return or emit a user-provided Parameterized-Type <T> require the user specify a means for constructing instances of 'T'. This class expects one of the two cases:

    • User-Provided Type <T> has a single argument constructor which accepts a JsonObject as a parameter. In this case, standard Java Reflection is used to retrieve and extract this constructor.

    • A Java Functional-Interface / Lambda be provided that accepts a JsonObject and returns an instance of User-Provided Type <T>. Building or generating an instance of <T> is acheived, simply, by invoking this function with the JsonObject which was extracted from the array.


    Method Parameters

    Parameter Explanation
    JsonArray ja This may be any parsed JsonArray whose contents are consistent with the Input-Parameters to the User-Provided Consumer.
    <T> defaultValue The only requirement is this value must be either an instance of 'T', or an instance of a child / inheriting type of 'T'.

    'null' may also be provided as a default value.
    String defaultValue Any Java String, or null, will suffice
    JsonObject defautValue
    JsonArray defautValue     		For either of these, any instance may be provided. Null is also allowed. Frequently it might be convenient to use the singleton, empty, instances provided by the Glass-Fish Implementation:

    JsonValue.EMPTY_JSON_OBJECT
    JsonValue.EMPTY_JSON_ARRAY
    int FLAGS A Bit-Wise Flag-Mask that provides a means for configuring the Array-Processing Logic to properly handle several types of Error-Cases & potentatial, unexpected, array contents.

    A Flag-Mask of '0' requests that any Error-Situations which occur, should they crop up while processing the array, be handled by standard means - meaning by throwing one of the germaine Exception-Classes.
    Class<T> consumerClass This may be any Java Class. It is required due to the limitations presented by Generic Erasure; this information is simply not available without providing a reference to this Class Object.
    java.util.function.Function
    <JsonObject, T> objBuilder         		When this parameter is present, it will be used to generate an instance of User-Specified Type 'T' by passing the JsonObject's encountered within the input array, to this user provided function.

    Lambda Signature:
    public <T> T apply(JsonObject jo)
    IntIntTFunc​ <JsonObject, T> objBuilder Similar to the above parameter, this object builder produces instances of User-Specified, Parameterized-Type 'T', but uses a @FunctionalInterface which accepts three parameters, intead of just the single JsonObject

    Lambda Signature:
    public <T> T apply(int jaIndex, int acceptorCount, JsonObject jo)

    The two "extra parameters" show above, are both primitive integers. The first one simply provides the JsonArray index where the object was found. The second 'int' contains the current iteration's "success count." These two numbers are usually identical; only cases where the user has specified a JFlag that requests the processor "Skip Entries on Failure" can These two integers take different values.
    java.util.function.Consumer
    <?> c         		For the methods in this class, once an object has been extracted & retrieved from the input JsonArray, it is then passed to this User-Provided Consumer. This is the how this class' name, "Into Consumer," was chosen.

    Lambda Signature:
    public void accept(<?> obj))
    IntIntTConsumer​ <?> c Almost identical to the one previous, this parameter acts as a User-Provided Consumer too. However, in addition to accepting the extracted 'T', String, JsonArray or JsonObject, instances of this consumer must implement a method which also accepts both the array index and the success count (often these two numbers are the same).

    Lambda Signature:
    public void accept(int jaIndex, int acceptorCount, <?> obj)

    The primary rationale for including an "extra" means for extracting data from an array is just to facilitate processing which may require information about where an object was located when it was extracted.
    See Also:
    Json, JsonArray



    Stateless Class:
    This class neither contains any program-state, nor can it be instantiated. The @StaticFunctional Annotation may also be called 'The Spaghetti Report'. Static-Functional classes are, essentially, C-Styled Files, without any constructors or non-static member fields. It is a concept very similar to the Java-Bean's @Stateless Annotation.

    • 1 Constructor(s), 1 declared private, zero-argument constructor
    • 12 Method(s), 12 declared static
    • 0 Field(s)


    • Method Detail

      • objArr

        🡇  ⇈  ⮫     External-Java:   ⮫  ⮫ 🗕  🗗  🗖 
        public static <T> void objArr​(JsonArray ja,
                              T defaultValue,
                              int FLAGS,
                              java.lang.Class<T> consumerClass,
                              java.util.function.Consumer<T> c)
        Read a JsonArray of JsonObject's into a Consumer<T>, Class 'T' must have a JsonObject-Constructor
        Invokes: Method ProcessJsonArray.objToJava(JsonArray, SettingsRec(T, Void)
        Passes: A pre-configured instance of SettingsRec<T, Void> to the ProcessJsonArray invocation.
        Expects: Parameterized Type <T> to be a Java Class / Type that has a single-argument constructor which accepts a JsonObject as a parameter.
        Sends: Generated Object is sent to the User-Provided Java Consumer<T> Parameter 'c'
        Code:
        Exact Method Body:
         ProcessJsonArray.objToJava(
     ja,
     new SETTINGS_REC_BUILDER<T, Void>
         (defaultValue, FLAGS, null, EXTENDED_TYPES.FROM_CTOR(consumerClass))
         .oneArgConsumer(c)
 );

      • objArr

        🡅  🡇  ⇈  ⮫     External-Java:   ⮫  ⮫ 🗕  🗗  🗖 
        public static <T> void objArr​
            (JsonArray ja,
             T defaultValue,
             int FLAGS,
             java.util.function.Function<JsonObject,​T> objBuilder,
             java.lang.Class<T> consumerClass,
             java.util.function.Consumer<T> c)
        Read a JsonArray of JsonObject's into a Consumer<T>, Parameter 'objBuilder' must generate instances of 'T'
        Invokes: Method ProcessJsonArray.objToJava(JsonArray, SettingsRec(T, Void)
        Passes: A pre-configured instance of SettingsRec<T, Void> to the ProcessJsonArray invocation.
        Expects: A Java Function<JsonObject, T> that will generate an instance of the expected output / emitted type <T>
        Type Note: Parameterized Type <T> may be any Java Object Class, not just a type which has a JsonObject Constructor.
        Sends: Generated Object is sent to the User-Provided Java Consumer<T> Parameter 'c'
        Code:
        Exact Method Body:
         ProcessJsonArray.objToJava(
     ja,
     new SETTINGS_REC_BUILDER<T, Void>
         (defaultValue, FLAGS, null, EXTENDED_TYPES.ONE_ARG_FUNC(objBuilder, consumerClass))
         .oneArgConsumer(c)
 );

      • objArr

        🡅  🡇  ⇈  ⮫     External-Java:   ⮫  ⮫ 🗕  🗗  🗖 
        public static <T> void objArr​(JsonArray ja,
                              T defaultValue,
                              int FLAGS,
                              IntIntTFunc<JsonObject,​T> objBuilder,
                              java.lang.Class<T> consumerClass,
                              java.util.function.Consumer<T> c)
        Read a JsonArray of JsonObject's into a Consumer<T>, Parameter 'objBuilder' must generate instances of 'T'
        Invokes: Method ProcessJsonArray.objToJava(JsonArray, SettingsRec(T, Void)
        Passes: A pre-configured instance of SettingsRec<T, Void> to the ProcessJsonArray invocation.
        Expects: An IntIntTFunc<JsonObject, T> that will generate an instance of the expected output / emitted type <T>
        Type Note: Parameterized Type <T> may be any Java Object Class, not just a type which has a JsonObject Constructor.
        Sends: Generated Object is sent to the User-Provided Java Consumer<T> Parameter 'c'
        Code:
        Exact Method Body:
         ProcessJsonArray.objToJava(
     ja,
     new SETTINGS_REC_BUILDER<T, Void>
         (defaultValue, FLAGS, null,
             EXTENDED_TYPES.THREE_ARG_FUNC(objBuilder, consumerClass))
         .oneArgConsumer(c)
 );

      • objArr2

        🡅  🡇  ⇈  ⮫     External-Java:   ⮫  ⮫ 🗕  🗗  🗖 
        public static <T> void objArr2​(JsonArray ja,
                               T defaultValue,
                               int FLAGS,
                               java.lang.Class<T> consumerClass,
                               IntIntTConsumer<T> c)
        Read a JsonArray of JsonObject's into an IntIntTConsumer<T>, Class 'T' must have a JsonObject-Constructor
        Invokes: Method ProcessJsonArray.objToJava(JsonArray, SettingsRec(T, Void)
        Passes: A pre-configured instance of SettingsRec<T, Void> to the ProcessJsonArray invocation.
        Expects: Parameterized Type <T> to be a Java Class / Type that has a single-argument constructor which accepts a JsonObject as a parameter.
        Sends: Generated Object is sent to the User-Provided Java-HTML IntIntTConsumer<T> Parameter 'c'
        Consumer-Signature: (Functional Interface) void accept (int jsonArrIndex, int acceptCount, T obj)
        Code:
        Exact Method Body:
         ProcessJsonArray.objToJava(
     ja,
     new SETTINGS_REC_BUILDER<T, Void>
         (defaultValue, FLAGS, null, EXTENDED_TYPES.FROM_CTOR(consumerClass))
         .threeArgConsumer(c)
 );

      • objArr2

        🡅  🡇  ⇈  ⮫     External-Java:   ⮫  ⮫ 🗕  🗗  🗖 
        public static <T> void objArr2​
            (JsonArray ja,
             T defaultValue,
             int FLAGS,
             java.util.function.Function<JsonObject,​T> objBuilder,
             java.lang.Class<T> consumerClass,
             IntIntTConsumer<T> c)
        Read a JsonArray of JsonObject's into an IntIntTConsumer<T>, Parameter 'objBuilder' must generate instances of 'T'
        Invokes: Method ProcessJsonArray.objToJava(JsonArray, SettingsRec(T, Void)
        Passes: A pre-configured instance of SettingsRec<T, Void> to the ProcessJsonArray invocation.
        Expects: A Java Function<JsonObject, T> that will generate an instance of the expected output / emitted type <T>
        Type Note: Parameterized Type <T> may be any Java Object Class, not just a type which has a JsonObject Constructor.
        Sends: Generated Object is sent to the User-Provided Java-HTML IntIntTConsumer<T> Parameter 'c'
        Consumer-Signature: (Functional Interface) void accept (int jsonArrIndex, int acceptCount, T obj)
        Code:
        Exact Method Body:
         ProcessJsonArray.objToJava(
     ja,
     new SETTINGS_REC_BUILDER<T, Void>
         (defaultValue, FLAGS, null, EXTENDED_TYPES.ONE_ARG_FUNC(objBuilder, consumerClass))
         .threeArgConsumer(c)
 );

      • objArr2

        🡅  🡇  ⇈  ⮫     External-Java:   ⮫  ⮫ 🗕  🗗  🗖 
        public static <T> void objArr2​(JsonArray ja,
                               T defaultValue,
                               int FLAGS,
                               IntIntTFunc<JsonObject,​T> objBuilder,
                               java.lang.Class<T> consumerClass,
                               IntIntTConsumer<T> c)
        Read a JsonArray of JsonObject's into an IntIntTConsumer<T>, Parameter 'objBuilder' must generate instances of 'T'
        Invokes: Method ProcessJsonArray.objToJava(JsonArray, SettingsRec(T, Void)
        Passes: A pre-configured instance of SettingsRec<T, Void> to the ProcessJsonArray invocation.
        Expects: An IntIntTFunc<JsonObject, T> that will generate an instance of the expected output / emitted type <T>
        Type Note: Parameterized Type <T> may be any Java Object Class, not just a type which has a JsonObject Constructor.
        Sends: Generated Object is sent to the User-Provided Java-HTML IntIntTConsumer<T> Parameter 'c'
        Consumer-Signature: (Functional Interface) void accept (int jsonArrIndex, int acceptCount, T obj)
        Code:
        Exact Method Body:
         ProcessJsonArray.objToJava(
     ja,
     new SETTINGS_REC_BUILDER<T, Void>
         (defaultValue, FLAGS, null, EXTENDED_TYPES
             .THREE_ARG_FUNC(objBuilder, consumerClass))
         .threeArgConsumer(c)
 );

      • strArr

        🡅  🡇  ⇈  ⮫     External-Java:   ⮫  ⮫ 🗕  🗗  🗖 
        public static void strArr​(JsonArray ja,
                          java.lang.String defaultValue,
                          int FLAGS,
                          java.util.function.Consumer<java.lang.String> c)
        Reads a JsonArray of String's into a Java Consumer<String>
        Invokes: Method ProcessJsonArray.strToJava(JsonArray, SettingsRec(T, Void)
        Passes: A pre-configured instance of SettingsRec<String, Void> to the ProcessJsonArray invocation.
        Sends: Retrieved / extracted String is sent to the User-Provided Java Consumer<String> Parameter 'c'
        Code:
        Exact Method Body:
         ProcessJsonArray.strToJava(
     ja,
     new SETTINGS_REC_BUILDER<String, Void>
         (defaultValue, FLAGS, null, BASIC_TYPES.STRING_REC())
         .oneArgConsumer(c)
 );

      • strArr2

        🡅  🡇  ⇈  ⮫     External-Java:   ⮫  ⮫ 🗕  🗗  🗖 
        public static void strArr2​(JsonArray ja,
                           java.lang.String defaultValue,
                           int FLAGS,
                           IntIntTConsumer<java.lang.String> c)
        Reads a JsonArray of String's into an IntIntTConsumer<String>
        Invokes: Method ProcessJsonArray.strToJava(JsonArray, SettingsRec(T, Void)
        Passes: A pre-configured instance of SettingsRec<String, Void> to the ProcessJsonArray invocation.
        Sends: Retrieved / extracted String is sent to the User-Provided Java-HTML IntIntTConsumer<String> Parameter 'c'
        Consumer-Signature: (Functional Interface) void accept (int jsonArrIndex, int acceptCount, String str)
        Code:
        Exact Method Body:
         ProcessJsonArray.strToJava(
     ja,
     new SETTINGS_REC_BUILDER<String, Void>
         (defaultValue, FLAGS, null, BASIC_TYPES.STRING_REC())
         .threeArgConsumer(c)
 );