Jackson Data Binding Source Code

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

  • Jackson Data Binding module allows you to converts JSON to and from POJO (Plain Old Java Object) using property accessor or using annotations.
  • Jackson Databind Source Code files are provided in the source packge (jackson-databind-2.12.4-sources.jar). You can download it at Jackson Maven Website.

    You can also browse Jackson Databind Source Code below:

    ✍: FYIcenter.com

    com/fasterxml/jackson/databind/type/CollectionLikeType.java

    package com.fasterxml.jackson.databind.type;
    
    import java.lang.reflect.TypeVariable;
    import java.util.Collection;
    
    import com.fasterxml.jackson.databind.JavaType;
    
    /**
     * Type that represents things that act similar to {@link java.util.Collection};
     * but may or may not be instances of that interface.
     * This specifically allows framework to check for configuration and annotation
     * settings used for Map types, and pass these to custom handlers that may be more
     * familiar with actual type.
     */
    public class CollectionLikeType extends TypeBase
    {
        private static final long serialVersionUID = 1L;
    
        /**
         * Type of elements in collection
         */
        protected final JavaType _elementType;
    
        /*
        /**********************************************************
        /* Life-cycle
        /**********************************************************
         */
    
        protected CollectionLikeType(Class<?> collT, TypeBindings bindings,
                JavaType superClass, JavaType[] superInts, JavaType elemT,
                Object valueHandler, Object typeHandler, boolean asStatic)
        {
            super(collT, bindings, superClass, superInts,
                    elemT.hashCode(), valueHandler, typeHandler, asStatic);
            _elementType = elemT;
        }
    
        /**
         * @since 2.7
         */
        protected CollectionLikeType(TypeBase base, JavaType elemT)
        {
            super(base);
            _elementType = elemT;
        }
    
        /**
         * @since 2.7
         */
        public static CollectionLikeType construct(Class<?> rawType, TypeBindings bindings,
                JavaType superClass, JavaType[] superInts, JavaType elemT) {
            return new CollectionLikeType(rawType, bindings, superClass, superInts, elemT,
                    null, null, false);
        }
    
        /**
         * @deprecated Since 2.7, use {@link #upgradeFrom} for constructing instances, given
         *    pre-resolved {@link SimpleType}.
         */
        @Deprecated // since 2.7
        public static CollectionLikeType construct(Class<?> rawType, JavaType elemT) {
            // First: may need to fabricate TypeBindings (needed for refining into
            // concrete collection types, as per [databind#1102])
            TypeVariable<?>[] vars = rawType.getTypeParameters();
            TypeBindings bindings;
            if ((vars == null) || (vars.length != 1)) {
                bindings = TypeBindings.emptyBindings();
            } else {
                bindings = TypeBindings.create(rawType, elemT);
            }
            return new CollectionLikeType(rawType, bindings,
                    _bogusSuperClass(rawType), null,
                    elemT, null, null, false);
        }
    
        /**
         * Factory method that can be used to "upgrade" a basic type into collection-like
         * one; usually done via {@link TypeModifier}
         *
         * @since 2.7
         */
        public static CollectionLikeType upgradeFrom(JavaType baseType, JavaType elementType) {
            // 19-Oct-2015, tatu: Not sure if and how other types could be used as base;
            //    will cross that bridge if and when need be
            if (baseType instanceof TypeBase) {
                return new CollectionLikeType((TypeBase) baseType, elementType);
            }
            throw new IllegalArgumentException("Cannot upgrade from an instance of "+baseType.getClass());
        }
    
        @Override
        @Deprecated // since 2.7
        protected JavaType _narrow(Class<?> subclass) {
            return new CollectionLikeType(subclass, _bindings,
                    _superClass, _superInterfaces, _elementType,
                    _valueHandler, _typeHandler, _asStatic);
        }
    
        @Override
        public JavaType withContentType(JavaType contentType) {
            if (_elementType == contentType) {
                return this;
            }
            return new CollectionLikeType(_class, _bindings, _superClass, _superInterfaces,
                    contentType, _valueHandler, _typeHandler, _asStatic);
        }
        
        @Override
        public CollectionLikeType withTypeHandler(Object h) {
            return new CollectionLikeType(_class, _bindings,
                    _superClass, _superInterfaces, _elementType, _valueHandler, h, _asStatic);
        }
    
        @Override
        public CollectionLikeType withContentTypeHandler(Object h)
        {
            return new CollectionLikeType(_class, _bindings,
                    _superClass, _superInterfaces, _elementType.withTypeHandler(h),
                    _valueHandler, _typeHandler, _asStatic);
        }
    
        @Override
        public CollectionLikeType withValueHandler(Object h) {
            return new CollectionLikeType(_class, _bindings,
                    _superClass, _superInterfaces, _elementType, h, _typeHandler, _asStatic);
        }
    
        @Override
        public CollectionLikeType withContentValueHandler(Object h) {
            return new CollectionLikeType(_class, _bindings,
                    _superClass, _superInterfaces, _elementType.withValueHandler(h),
                    _valueHandler, _typeHandler, _asStatic);
        }
    
        @Override
        public JavaType withHandlersFrom(JavaType src) {
            JavaType type = super.withHandlersFrom(src);
            JavaType srcCt = src.getContentType();
            if (srcCt != null) {
                JavaType ct = _elementType.withHandlersFrom(srcCt);
                if (ct != _elementType) {
                    type = type.withContentType(ct);
                }
            }
            return type;
        }
        
        @Override
        public CollectionLikeType withStaticTyping() {
            if (_asStatic) {
                return this;
            }
            return new CollectionLikeType(_class, _bindings,
                    _superClass, _superInterfaces, _elementType.withStaticTyping(),
                    _valueHandler, _typeHandler, true);
        }
    
        @Override
        public JavaType refine(Class<?> rawType, TypeBindings bindings,
                JavaType superClass, JavaType[] superInterfaces) {
            return new CollectionLikeType(rawType, bindings,
                    superClass, superInterfaces, _elementType,
                    _valueHandler, _typeHandler, _asStatic);
        }
        
        /*
        /**********************************************************
        /* Public API
        /**********************************************************
         */
    
        @Override
        public boolean isContainerType() { return true; }
    
        @Override
        public boolean isCollectionLikeType() { return true; }
    
        @Override
        public JavaType getContentType() { return _elementType; }
    
        @Override
        public Object getContentValueHandler() {
            return _elementType.getValueHandler();
        }
    
        @Override
        public Object getContentTypeHandler() {
            return _elementType.getTypeHandler();
        }    
    
        @Override
        public boolean hasHandlers() {
            return super.hasHandlers() || _elementType.hasHandlers();
        }
    
        @Override
        public StringBuilder getErasedSignature(StringBuilder sb) {
            return _classSignature(_class, sb, true);
        }
        
        @Override
        public StringBuilder getGenericSignature(StringBuilder sb) {
            _classSignature(_class, sb, false);
            sb.append('<');
            _elementType.getGenericSignature(sb);
            sb.append(">;");
            return sb;
        }
        
        @Override
        protected String buildCanonicalName() {
            StringBuilder sb = new StringBuilder();
            sb.append(_class.getName());
            // 10-Apr-2021, tatu: [databind#3108] Ensure we have at least nominally
            //   compatible type declaration (weak guarantee but better than nothing)
            if ((_elementType != null) && _hasNTypeParameters(1)) {
                sb.append('<');
                sb.append(_elementType.toCanonical());
                sb.append('>');
            }
            return sb.toString();
        }
    
        /*
        /**********************************************************
        /* Extended API
        /**********************************************************
         */
    
        /**
         * Method that can be used for checking whether this type is a
         * "real" Collection type; meaning whether it represents a parameterized
         * subtype of {@link java.util.Collection} or just something that acts
         * like one.
         *
         * @deprecated Since 2.12 just use instanceof 
         */
        @Deprecated // since 2.12 use assignment checks
        public boolean isTrueCollectionType() {
            return Collection.class.isAssignableFrom(_class);
        }
    
        /*
        /**********************************************************
        /* Standard methods
        /**********************************************************
         */
    
        @Override
        public boolean equals(Object o)
        {
            if (o == this) return true;
            if (o == null) return false;
            if (o.getClass() != getClass()) return false;
    
            CollectionLikeType other = (CollectionLikeType) o;
            return  (_class == other._class) && _elementType.equals(other._elementType);
        }
    
        @Override
        public String toString()
        {
            return "[collection-like type; class "+_class.getName()+", contains "+_elementType+"]";
        }
    
    }
    

    com/fasterxml/jackson/databind/type/CollectionLikeType.java

     

    ⇒ Jackson Annotations Source Code

    ⇐ Download and Install Jackson Binary Package

    ⇑ Downloading and Reviewing jackson-*.jar

    ⇑⇑ Jackson - Java JSON library

    2022-03-29, 32035👍, 0💬