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package com.fasterxml.jackson.databind;

import java.lang.reflect.Type;
import java.util.Locale;
import java.util.TimeZone;

import com.fasterxml.jackson.annotation.*;

import com.fasterxml.jackson.databind.cfg.HandlerInstantiator;
import com.fasterxml.jackson.databind.cfg.MapperConfig;
import com.fasterxml.jackson.databind.introspect.Annotated;
import com.fasterxml.jackson.databind.introspect.ObjectIdInfo;
import com.fasterxml.jackson.databind.type.TypeFactory;
import com.fasterxml.jackson.databind.util.ClassUtil;
import com.fasterxml.jackson.databind.util.Converter;

/**
 * Shared base class for {@link DeserializationContext} and
 * {@link SerializerProvider}, context objects passed through data-binding
 * process. Designed so that some of implementations can rely on shared
 * aspects like access to secondary contextual objects like type factories
 * or handler instantiators.
 * 
 * @since 2.2
 */
public abstract class DatabindContext
{
    /**
     * Let's limit length of error messages, for cases where underlying data
     * may be very large -- no point in spamming logs with megabytes of meaningless
     * data.
     *
     * @since 2.9
     */
    private final static int MAX_ERROR_STR_LEN = 500;

    /*
    /**********************************************************
    /* Generic config access
    /**********************************************************
     */

    /**
     * Accessor to currently active configuration (both per-request configs
     * and per-mapper config).
     */
    public abstract MapperConfig getConfig();

    /**
     * Convenience method for accessing serialization view in use (if any); equivalent to:
     *
     *   getConfig().getAnnotationIntrospector();
     *
*/ public abstract AnnotationIntrospector getAnnotationIntrospector(); /* /********************************************************** /* Access to specific config settings /********************************************************** */ /** * Convenience method for checking whether specified serialization * feature is enabled or not. * Shortcut for: *
     *  getConfig().isEnabled(feature);
     *
*/ public abstract boolean isEnabled(MapperFeature feature); /** * Convenience method for accessing serialization view in use (if any); equivalent to: *
     *   getConfig().canOverrideAccessModifiers();
     *
*/ public abstract boolean canOverrideAccessModifiers(); /** * Accessor for locating currently active view, if any; * returns null if no view has been set. */ public abstract Class getActiveView(); /** * @since 2.6 */ public abstract Locale getLocale(); /** * @since 2.6 */ public abstract TimeZone getTimeZone(); /** * @since 2.7 */ public abstract JsonFormat.Value getDefaultPropertyFormat(Class baseType); /* /********************************************************** /* Generic attributes (2.3+) /********************************************************** */ /** * Method for accessing attributes available in this context. * Per-call attributes have highest precedence; attributes set * via {@link ObjectReader} or {@link ObjectWriter} have lower * precedence. * * @param key Key of the attribute to get * @return Value of the attribute, if any; null otherwise * * @since 2.3 */ public abstract Object getAttribute(Object key); /** * Method for setting per-call value of given attribute. * This will override any previously defined value for the * attribute within this context. * * @param key Key of the attribute to set * @param value Value to set attribute to * * @return This context object, to allow chaining * * @since 2.3 */ public abstract DatabindContext setAttribute(Object key, Object value); /* /********************************************************** /* Type instantiation/resolution /********************************************************** */ /** * Convenience method for constructing {@link JavaType} for given JDK * type (usually {@link java.lang.Class}) */ public JavaType constructType(Type type) { if (type == null) { return null; } return getTypeFactory().constructType(type); } /** * Convenience method for constructing subtypes, retaining generic * type parameter (if any) */ public JavaType constructSpecializedType(JavaType baseType, Class subclass) { // simple optimization to avoid costly introspection if type-erased type does NOT differ if (baseType.getRawClass() == subclass) { return baseType; } return getConfig().constructSpecializedType(baseType, subclass); } /** * Lookup method called when code needs to resolve class name from input; * usually simple lookup * * @since 2.9 */ public JavaType resolveSubType(JavaType baseType, String subClass) throws JsonMappingException { // 30-Jan-2010, tatu: Most ids are basic class names; so let's first // check if any generics info is added; and only then ask factory // to do translation when necessary if (subClass.indexOf('<') > 0) { // note: may want to try combining with specialization (esp for EnumMap)? // 17-Aug-2017, tatu: As per [databind#1735] need to ensure assignment // compatibility -- needed later anyway, and not doing so may open // security issues. JavaType t = getTypeFactory().constructFromCanonical(subClass); if (t.isTypeOrSubTypeOf(baseType.getRawClass())) { return t; } } else { Class cls; try { cls = getTypeFactory().findClass(subClass); } catch (ClassNotFoundException e) { // let caller handle this problem return null; } catch (Exception e) { throw invalidTypeIdException(baseType, subClass, String.format( "problem: (%s) %s", e.getClass().getName(), e.getMessage())); } if (baseType.isTypeOrSuperTypeOf(cls)) { return getTypeFactory().constructSpecializedType(baseType, cls); } } throw invalidTypeIdException(baseType, subClass, "Not a subtype"); } /** * Helper method for constructing exception to indicate that given type id * could not be resolved to a valid subtype of specified base type. * Most commonly called during polymorphic deserialization. *

* Note that most of the time this method should NOT be called directly: instead, * method handleUnknownTypeId() should be called which will call this method * if necessary. * * @since 2.9 */ protected abstract JsonMappingException invalidTypeIdException(JavaType baseType, String typeId, String extraDesc); public abstract TypeFactory getTypeFactory(); /* /********************************************************** /* Helper object construction /********************************************************** */ public ObjectIdGenerator objectIdGeneratorInstance(Annotated annotated, ObjectIdInfo objectIdInfo) throws JsonMappingException { Class implClass = objectIdInfo.getGeneratorType(); final MapperConfig config = getConfig(); HandlerInstantiator hi = config.getHandlerInstantiator(); ObjectIdGenerator gen = (hi == null) ? null : hi.objectIdGeneratorInstance(config, annotated, implClass); if (gen == null) { gen = (ObjectIdGenerator) ClassUtil.createInstance(implClass, config.canOverrideAccessModifiers()); } return gen.forScope(objectIdInfo.getScope()); } public ObjectIdResolver objectIdResolverInstance(Annotated annotated, ObjectIdInfo objectIdInfo) { Class implClass = objectIdInfo.getResolverType(); final MapperConfig config = getConfig(); HandlerInstantiator hi = config.getHandlerInstantiator(); ObjectIdResolver resolver = (hi == null) ? null : hi.resolverIdGeneratorInstance(config, annotated, implClass); if (resolver == null) { resolver = ClassUtil.createInstance(implClass, config.canOverrideAccessModifiers()); } return resolver; } /** * Helper method to use to construct a {@link Converter}, given a definition * that may be either actual converter instance, or Class for instantiating one. * * @since 2.2 */ @SuppressWarnings("unchecked") public Converter converterInstance(Annotated annotated, Object converterDef) throws JsonMappingException { if (converterDef == null) { return null; } if (converterDef instanceof Converter) { return (Converter) converterDef; } if (!(converterDef instanceof Class)) { throw new IllegalStateException("AnnotationIntrospector returned Converter definition of type " +converterDef.getClass().getName()+"; expected type Converter or Class instead"); } Class converterClass = (Class)converterDef; // there are some known "no class" markers to consider too: if (converterClass == Converter.None.class || ClassUtil.isBogusClass(converterClass)) { return null; } if (!Converter.class.isAssignableFrom(converterClass)) { throw new IllegalStateException("AnnotationIntrospector returned Class " +converterClass.getName()+"; expected Class"); } final MapperConfig config = getConfig(); HandlerInstantiator hi = config.getHandlerInstantiator(); Converter conv = (hi == null) ? null : hi.converterInstance(config, annotated, converterClass); if (conv == null) { conv = (Converter) ClassUtil.createInstance(converterClass, config.canOverrideAccessModifiers()); } return (Converter) conv; } /* /********************************************************** /* Error reporting /********************************************************** */ /** * Helper method called to indicate a generic problem that stems from type * definition(s), not input data, or input/output state; typically this * means throwing a {@link com.fasterxml.jackson.databind.exc.InvalidDefinitionException}. * * @since 2.9 */ public abstract T reportBadDefinition(JavaType type, String msg) throws JsonMappingException; /** * @since 2.9 */ public T reportBadDefinition(Class type, String msg) throws JsonMappingException { return reportBadDefinition(constructType(type), msg); } /* /********************************************************** /* Helper methods /********************************************************** */ /** * @since 2.9 */ protected final String _format(String msg, Object... msgArgs) { if (msgArgs.length > 0) { return String.format(msg, msgArgs); } return msg; } /** * @since 2.9 */ protected final String _truncate(String desc) { if (desc == null) { return ""; } if (desc.length() <= MAX_ERROR_STR_LEN) { return desc; } return desc.substring(0, MAX_ERROR_STR_LEN) + "]...[" + desc.substring(desc.length() - MAX_ERROR_STR_LEN); } /** * @since 2.9 */ protected String _quotedString(String desc) { if (desc == null) { return "[N/A]"; } // !!! should we quote it? (in case there are control chars, linefeeds) return String.format("\"%s\"", _truncate(desc)); } /** * @since 2.9 */ protected String _colonConcat(String msgBase, String extra) { if (extra == null) { return msgBase; } return msgBase + ": " + extra; } /** * @since 2.9 */ protected String _desc(String desc) { if (desc == null) { return "[N/A]"; } // !!! should we quote it? (in case there are control chars, linefeeds) return _truncate(desc); } }





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