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

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

You can also browse Jackson Databind Source Code below:

⏎ com/fasterxml/jackson/databind/type/ArrayType.java

package com.fasterxml.jackson.databind.type;

import java.lang.reflect.Array;

import com.fasterxml.jackson.databind.JavaType;

/**
 * Array types represent Java arrays, both primitive and object valued.
 * Further, Object-valued arrays can have element type of any other
 * legal {@link JavaType}.
 */
public final class ArrayType
    extends TypeBase
{
    private static final long serialVersionUID = 1L;

    /**
     * Type of elements in the array.
     */
    protected final JavaType _componentType;

    /**
     * We will also keep track of shareable instance of empty array,
     * since it usually needs to be constructed any way; and because
     * it is essentially immutable and thus can be shared.
     */
    protected final Object _emptyArray;

    protected ArrayType(JavaType componentType, TypeBindings bindings, Object emptyInstance,
            Object valueHandler, Object typeHandler, boolean asStatic)
    {
        // No super-class, interfaces, for now
        super(emptyInstance.getClass(), bindings, null, null,
                componentType.hashCode(),
                valueHandler, typeHandler, asStatic);
        _componentType = componentType;
        _emptyArray = emptyInstance;
    }

    public static ArrayType construct(JavaType componentType, TypeBindings bindings) {
        return construct(componentType, bindings, null, null);
    }

    public static ArrayType construct(JavaType componentType, TypeBindings bindings,
            Object valueHandler, Object typeHandler) {
        // Figuring out raw class for generic array is actually bit tricky...
        Object emptyInstance = Array.newInstance(componentType.getRawClass(), 0);
        return new ArrayType(componentType, bindings, emptyInstance, valueHandler, typeHandler, false);
    }

    @Override
    public JavaType withContentType(JavaType contentType) {
        Object emptyInstance = Array.newInstance(contentType.getRawClass(), 0);
        return new ArrayType(contentType, _bindings, emptyInstance,
                _valueHandler, _typeHandler, _asStatic);
    }

    @Override
    public ArrayType withTypeHandler(Object h)
    {
        if (h == _typeHandler) {
            return this;
        }
        return new ArrayType(_componentType, _bindings, _emptyArray, _valueHandler, h, _asStatic);
    }

    @Override
    public ArrayType withContentTypeHandler(Object h)
    {
        if (h == _componentType.<Object>getTypeHandler()) {
            return this;
        }
        return new ArrayType(_componentType.withTypeHandler(h), _bindings, _emptyArray,
                _valueHandler, _typeHandler, _asStatic);
    }

    @Override
    public ArrayType withValueHandler(Object h) {
        if (h == _valueHandler) {
            return this;
        }
        return new ArrayType(_componentType, _bindings, _emptyArray, h, _typeHandler,_asStatic);
    }

    @Override
    public ArrayType withContentValueHandler(Object h) {
        if (h == _componentType.<Object>getValueHandler()) {
            return this;
        }
        return new ArrayType(_componentType.withValueHandler(h), _bindings, _emptyArray,
                _valueHandler, _typeHandler, _asStatic);
    }

    @Override
    public ArrayType withStaticTyping() {
        if (_asStatic) {
            return this;
        }
        return new ArrayType(_componentType.withStaticTyping(), _bindings,
                _emptyArray, _valueHandler, _typeHandler, true);
    }

    /*
    /**********************************************************
    /* Methods for narrowing conversions
    /**********************************************************
     */

    /**
     * Handling of narrowing conversions for arrays is trickier: for now,
     * it is not even allowed.
     */
    @Override
    @Deprecated // since 2.7
    protected JavaType _narrow(Class<?> subclass) {
        return _reportUnsupported();
    }

    // Should not be called, as array types in Java are not extensible; but
    // let's not freak out even if it is called?
    @Override
    public JavaType refine(Class<?> contentClass, TypeBindings bindings,
            JavaType superClass, JavaType[] superInterfaces) {
        return null;
    }

    private JavaType _reportUnsupported() {
        throw new UnsupportedOperationException("Cannot narrow or widen array types");
    }

    /*
    /**********************************************************
    /* Overridden methods
    /**********************************************************
     */

    @Override
    public boolean isArrayType() { return true; }
    
    /**
     * For some odd reason, modifiers for array classes would
     * claim they are abstract types. Not so, at least for our
     * purposes.
     */
    @Override
    public boolean isAbstract() { return false; }

    /**
     * For some odd reason, modifiers for array classes would
     * claim they are abstract types. Not so, at least for our
     * purposes.
     */
    @Override
    public boolean isConcrete() { return true; }

    @Override
    public boolean hasGenericTypes() {
        // arrays are not parameterized, but element type may be:
        return _componentType.hasGenericTypes();
    }

    /*
    /**********************************************************
    /* Public API
    /**********************************************************
     */

    @Override
    public boolean isContainerType() { return true; }

    @Override
    public JavaType getContentType() { return  _componentType; }

    @Override
    public Object getContentValueHandler() {
        return _componentType.getValueHandler();
    }

    @Override
    public Object getContentTypeHandler() {
        return _componentType.getTypeHandler();
    }

    @Override
    public boolean hasHandlers() {
        return super.hasHandlers() || _componentType.hasHandlers();
    }
    
    @Override
    public StringBuilder getGenericSignature(StringBuilder sb) {
        sb.append('[');
        return _componentType.getGenericSignature(sb);
    }

    @Override
    public StringBuilder getErasedSignature(StringBuilder sb) {
        sb.append('[');
        return _componentType.getErasedSignature(sb);
    }

    /*
    /**********************************************************
    /* Extended API
    /**********************************************************
     */

    /**
     * @since 2.12
     */
    public Object[] getEmptyArray() {
        return  (Object[]) _emptyArray;
    }

    /*
    /**********************************************************
    /* Standard methods
    /**********************************************************
     */

    @Override
    public String toString()
    {
        return "[array type, component type: "+_componentType+"]";
    }

    @Override
    public boolean equals(Object o)
    {
        if (o == this) return true;
        if (o == null) return false;
        if (o.getClass() != getClass()) return false;

        ArrayType other = (ArrayType) o;
        return _componentType.equals(other._componentType);
    }
}

⏎ com/fasterxml/jackson/databind/type/ArrayType.java

Or download all of them as a single archive file:

File name: jackson-databind-2.14.0-sources.jar
File size: 1187952 bytes
Release date: 2022-11-05
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