Jackson is "the Java JSON library" or "the best JSON parser for Java". Or simply as "JSON for Java".

Jackson Core Source Code files are provided in the source packge (jackson-core-2.14.0-sources.jar). You can download it at Jackson Maven Website.

You can also browse Jackson Core Source Code below:

⏎ com/fasterxml/jackson/core/TSFBuilder.java

package com.fasterxml.jackson.core;

import com.fasterxml.jackson.core.io.InputDecorator;
import com.fasterxml.jackson.core.io.OutputDecorator;
import com.fasterxml.jackson.core.json.JsonReadFeature;
import com.fasterxml.jackson.core.json.JsonWriteFeature;

/**
 * Since 2.10, Builder class is offered for creating token stream factories
 * with difference configurations: with 3.x they will be fully immutable.
 *
 * @since 2.10
 */
public abstract class TSFBuilder<F extends JsonFactory,
    B extends TSFBuilder<F,B>>
{
    /*
    /**********************************************************************
    /* Constants
    /**********************************************************************
     */

    /**
     * Bitfield (set of flags) of all factory features that are enabled by default.
     */
    protected final static int DEFAULT_FACTORY_FEATURE_FLAGS = JsonFactory.Feature.collectDefaults();

    /**
     * Bitfield (set of flags) of all parser features that are enabled
     * by default.
     */
    protected final static int DEFAULT_PARSER_FEATURE_FLAGS = JsonParser.Feature.collectDefaults();
    
    /**
     * Bitfield (set of flags) of all generator features that are enabled
     * by default.
     */
    protected final static int DEFAULT_GENERATOR_FEATURE_FLAGS = JsonGenerator.Feature.collectDefaults();

    /*
    /**********************************************************************
    /* Configured features
    /**********************************************************************
     */

    /**
     * Set of {@link com.fasterxml.jackson.core.JsonFactory.Feature}s enabled,
     * as bitmask.
     */
    protected int _factoryFeatures;

    /**
     * Set of {@link JsonParser.Feature}s enabled, as bitmask.
     */
    protected int _streamReadFeatures;

    /**
     * Set of {@link JsonGenerator.Feature}s enabled, as bitmask.
     */
    protected int _streamWriteFeatures;

    /*
    /**********************************************************************
    /* Other configuration
    /**********************************************************************
     */

    /**
     * Optional helper object that may decorate input sources, to do
     * additional processing on input during parsing.
     */
    protected InputDecorator _inputDecorator;

    /**
     * Optional helper object that may decorate output object, to do
     * additional processing on output during content generation.
     */
    protected OutputDecorator _outputDecorator;
    
    /*
    /**********************************************************************
    /* Construction
    /**********************************************************************
     */

    protected TSFBuilder() {
        _factoryFeatures = DEFAULT_FACTORY_FEATURE_FLAGS;
        _streamReadFeatures = DEFAULT_PARSER_FEATURE_FLAGS;
        _streamWriteFeatures = DEFAULT_GENERATOR_FEATURE_FLAGS;
        _inputDecorator = null;
        _outputDecorator = null;
    }

    protected TSFBuilder(JsonFactory base)
    {
        this(base._factoryFeatures,
                base._parserFeatures, base._generatorFeatures);
    }

    protected TSFBuilder(int factoryFeatures,
            int parserFeatures, int generatorFeatures)
    {
        _factoryFeatures = factoryFeatures;
        _streamReadFeatures = parserFeatures;
        _streamWriteFeatures = generatorFeatures;
    }

    // // // Accessors

    public int factoryFeaturesMask() { return _factoryFeatures; }
    public int streamReadFeatures() { return _streamReadFeatures; }
    public int streamWriteFeatures() { return _streamWriteFeatures; }

    public InputDecorator inputDecorator() { return _inputDecorator; }
    public OutputDecorator outputDecorator() { return _outputDecorator; }

    // // // Factory features

    public B enable(JsonFactory.Feature f) {
        _factoryFeatures |= f.getMask();
        return _this();
    }

    public B disable(JsonFactory.Feature f) {
        _factoryFeatures &= ~f.getMask();
        return _this();
    }

    public B configure(JsonFactory.Feature f, boolean state) {
        return state ? enable(f) : disable(f);
    }

    // // // StreamReadFeatures (replacement of non-json-specific parser features)

    public B enable(StreamReadFeature f) {
        _streamReadFeatures |= f.mappedFeature().getMask();
        return _this();
    }

    public B enable(StreamReadFeature first, StreamReadFeature... other) {
        _streamReadFeatures |= first.mappedFeature().getMask();
        for (StreamReadFeature f : other) {
            _streamReadFeatures |= f.mappedFeature().getMask();
        }
        return _this();
    }

    public B disable(StreamReadFeature f) {
        _streamReadFeatures &= ~f.mappedFeature().getMask();
        return _this();
    }

    public B disable(StreamReadFeature first, StreamReadFeature... other) {
        _streamReadFeatures &= ~first.mappedFeature().getMask();
        for (StreamReadFeature f : other) {
            _streamReadFeatures &= ~f.mappedFeature().getMask();
        }
        return _this();
    }

    public B configure(StreamReadFeature f, boolean state) {
        return state ? enable(f) : disable(f);
    }

    // // // StreamWriteFeatures (replacement of non-json-specific generator features)

    public B enable(StreamWriteFeature f) {
        _streamWriteFeatures |= f.mappedFeature().getMask();
        return _this();
    }

    public B enable(StreamWriteFeature first, StreamWriteFeature... other) {
        _streamWriteFeatures |= first.mappedFeature().getMask();
        for (StreamWriteFeature f : other) {
            _streamWriteFeatures |= f.mappedFeature().getMask();
        }
        return _this();
    }

    public B disable(StreamWriteFeature f) {
        _streamWriteFeatures &= ~f.mappedFeature().getMask();
        return _this();
    }
    
    public B disable(StreamWriteFeature first, StreamWriteFeature... other) {
        _streamWriteFeatures &= ~first.mappedFeature().getMask();
        for (StreamWriteFeature f : other) {
            _streamWriteFeatures &= ~f.mappedFeature().getMask();
        }
        return _this();
    }

    public B configure(StreamWriteFeature f, boolean state) {
        return state ? enable(f) : disable(f);
    }

    /* 26-Jun-2018, tatu: This should not be needed here, but due to 2.x limitations,
     *   we do need to include it or require casting.
     *   Specifically: since `JsonFactory` (and not `TokenStreamFactory`) is base class
     *   for all backends, it can not expose JSON-specific builder, but this.
     *   So let's select lesser evil(s).
     */

    // // // JSON-specific, reads

    public B enable(JsonReadFeature f) {
        return _failNonJSON(f);
    }

    public B enable(JsonReadFeature first, JsonReadFeature... other) {
        return _failNonJSON(first);
    }

    public B disable(JsonReadFeature f) {
        return _failNonJSON(f);
    }

    public B disable(JsonReadFeature first, JsonReadFeature... other) {
        return _failNonJSON(first);
    }

    public B configure(JsonReadFeature f, boolean state) {
        return _failNonJSON(f);
    }
    
    private B _failNonJSON(Object feature) {
        throw new IllegalArgumentException("Feature "+feature.getClass().getName()
                +"#"+feature.toString()+" not supported for non-JSON backend");
    }

    // // // JSON-specific, writes

    public B enable(JsonWriteFeature f) {
        return _failNonJSON(f);
    }

    public B enable(JsonWriteFeature first, JsonWriteFeature... other) {
        return _failNonJSON(first);
    }

    public B disable(JsonWriteFeature f) {
        return _failNonJSON(f);
    }

    public B disable(JsonWriteFeature first, JsonWriteFeature... other) {
        return _failNonJSON(first);
    }

    public B configure(JsonWriteFeature f, boolean state) {
        return _failNonJSON(f);
    }

    // // // Other configuration

    public B inputDecorator(InputDecorator dec) {
        _inputDecorator = dec;
        return _this();
    }

    public B outputDecorator(OutputDecorator dec) {
        _outputDecorator = dec;
        return _this();
    }

    // // // Other methods

    /**
     * Method for constructing actual {@link TokenStreamFactory} instance, given
     * configuration.
     *
     * @return {@link TokenStreamFactory} build based on current configuration
     */
    public abstract F build();

    // silly convenience cast method we need
    @SuppressWarnings("unchecked")
    protected final B _this() { return (B) this; }

    // // // Support for subtypes

    protected void _legacyEnable(JsonParser.Feature f) {
        if (f != null) {
            _streamReadFeatures |= f.getMask();
        }
    }

    protected void _legacyDisable(JsonParser.Feature f) {
        if (f != null) {
            _streamReadFeatures &= ~f.getMask();
        }
    }

    protected void _legacyEnable(JsonGenerator.Feature f) {
        if (f != null) {
            _streamWriteFeatures |= f.getMask();
        }
    }
    protected void _legacyDisable(JsonGenerator.Feature f) {
        if (f != null) {
            _streamWriteFeatures &= ~f.getMask();
        }
    }
}

⏎ com/fasterxml/jackson/core/TSFBuilder.java

Or download all of them as a single archive file:

File name: jackson-core-2.14.0-sources.jar
File size: 497693 bytes
Release date: 2022-11-05
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