package com.fasterxml.jackson.databind.deser.impl;

import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.util.*;

import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.JsonDeserializer;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.PropertyName;
import com.fasterxml.jackson.databind.deser.SettableBeanProperty;
import com.fasterxml.jackson.databind.util.ClassUtil;
import com.fasterxml.jackson.databind.util.NameTransformer;

Helper class used for storing mapping from property name to SettableBeanProperty instances.

Note that this class is used instead of generic HashMap for bit of performance gain (and some memory savings): although default implementation is very good for generic use cases, it can be streamlined a bit for specific use case we have. Even relatively small improvements matter since this is directly on the critical path during deserialization, as it is done for each and every POJO property deserialized.

/** * Helper class used for storing mapping from property name to * {@link SettableBeanProperty} instances. *<p> * Note that this class is used instead of generic {@link java.util.HashMap} * for bit of performance gain (and some memory savings): although default * implementation is very good for generic use cases, it can be streamlined * a bit for specific use case we have. Even relatively small improvements * matter since this is directly on the critical path during deserialization, * as it is done for each and every POJO property deserialized. */
public class BeanPropertyMap implements Iterable<SettableBeanProperty>, java.io.Serializable { private static final long serialVersionUID = 2L;
Since:2.5
/** * @since 2.5 */
protected final boolean _caseInsensitive; private int _hashMask;
Number of entries stored in the hash area.
/** * Number of entries stored in the hash area. */
private int _size; private int _spillCount;
Hash area that contains key/property pairs in adjacent elements.
/** * Hash area that contains key/property pairs in adjacent elements. */
private Object[] _hashArea;
Array of properties in the exact order they were handed in. This is used by as-array serialization, deserialization.
/** * Array of properties in the exact order they were handed in. This is * used by as-array serialization, deserialization. */
private final SettableBeanProperty[] _propsInOrder;
Configuration of alias mappings, indexed by unmodified property name to unmodified aliases, if any; entries only included for properties that do have aliases. This is is used for constructing actual reverse lookup mapping, if needed, taking into account possible case-insensitivity, as well as possibility of name prefixes.
Since:2.9
/** * Configuration of alias mappings, indexed by unmodified property name * to unmodified aliases, if any; entries only included for properties * that do have aliases. * This is is used for constructing actual reverse lookup mapping, if * needed, taking into account possible case-insensitivity, as well * as possibility of name prefixes. * * @since 2.9 */
private final Map<String,List<PropertyName>> _aliasDefs;
Mapping from secondary names (aliases) to primary names.
Since:2.9
/** * Mapping from secondary names (aliases) to primary names. * * @since 2.9 */
private final Map<String,String> _aliasMapping;
Since:2.9
/** * @since 2.9 */
public BeanPropertyMap(boolean caseInsensitive, Collection<SettableBeanProperty> props, Map<String,List<PropertyName>> aliasDefs) { _caseInsensitive = caseInsensitive; _propsInOrder = props.toArray(new SettableBeanProperty[props.size()]); _aliasDefs = aliasDefs; _aliasMapping = _buildAliasMapping(aliasDefs); init(props); } /* Copy constructors used when a property can replace existing one * * @since 2.9.6 */ private BeanPropertyMap(BeanPropertyMap src, SettableBeanProperty newProp, int hashIndex, int orderedIndex) { // First, copy most fields as is: _caseInsensitive = src._caseInsensitive; _hashMask = src._hashMask; _size = src._size; _spillCount = src._spillCount; _aliasDefs = src._aliasDefs; _aliasMapping = src._aliasMapping; // but then make deep copy of arrays to modify _hashArea = Arrays.copyOf(src._hashArea, src._hashArea.length); _propsInOrder = Arrays.copyOf(src._propsInOrder, src._propsInOrder.length); _hashArea[hashIndex] = newProp; _propsInOrder[orderedIndex] = newProp; } /* Copy constructors used when a property needs to be appended (can't replace) * * @since 2.9.6 */ private BeanPropertyMap(BeanPropertyMap src, SettableBeanProperty newProp, String key, int slot) { // First, copy most fields as is: _caseInsensitive = src._caseInsensitive; _hashMask = src._hashMask; _size = src._size; _spillCount = src._spillCount; _aliasDefs = src._aliasDefs; _aliasMapping = src._aliasMapping; // but then make deep copy of arrays to modify _hashArea = Arrays.copyOf(src._hashArea, src._hashArea.length); int last = src._propsInOrder.length; // and append property at the end of ordering _propsInOrder = Arrays.copyOf(src._propsInOrder, last+1); _propsInOrder[last] = newProp; final int hashSize = _hashMask+1; int ix = (slot<<1); // primary slot not free? if (_hashArea[ix] != null) { // secondary? ix = (hashSize + (slot >> 1)) << 1; if (_hashArea[ix] != null) { // ok, spill over. ix = ((hashSize + (hashSize >> 1) ) << 1) + _spillCount; _spillCount += 2; if (ix >= _hashArea.length) { _hashArea = Arrays.copyOf(_hashArea, _hashArea.length + 4); } } } _hashArea[ix] = key; _hashArea[ix+1] = newProp; } @Deprecated // since 2.8 public BeanPropertyMap(boolean caseInsensitive, Collection<SettableBeanProperty> props) { this(caseInsensitive, props, Collections.<String,List<PropertyName>>emptyMap()); }
Since:2.8
/** * @since 2.8 */
protected BeanPropertyMap(BeanPropertyMap base, boolean caseInsensitive) { _caseInsensitive = caseInsensitive; _aliasDefs = base._aliasDefs; _aliasMapping = base._aliasMapping; // 16-May-2016, tatu: Alas, not enough to just change flag, need to re-init as well. _propsInOrder = Arrays.copyOf(base._propsInOrder, base._propsInOrder.length); init(Arrays.asList(_propsInOrder)); }
Mutant factory method that constructs a new instance if desired case-insensitivity state differs from the state of this instance; if states are the same, returns this.
Since:2.8
/** * Mutant factory method that constructs a new instance if desired case-insensitivity * state differs from the state of this instance; if states are the same, returns * <code>this</code>. * * @since 2.8 */
public BeanPropertyMap withCaseInsensitivity(boolean state) { if (_caseInsensitive == state) { return this; } return new BeanPropertyMap(this, state); } protected void init(Collection<SettableBeanProperty> props) { _size = props.size(); // First: calculate size of primary hash area final int hashSize = findSize(_size); _hashMask = hashSize-1; // and allocate enough to contain primary/secondary, expand for spillovers as need be int alloc = (hashSize + (hashSize>>1)) * 2; Object[] hashed = new Object[alloc]; int spillCount = 0; for (SettableBeanProperty prop : props) { // Due to removal, renaming, theoretically possible we'll have "holes" so: if (prop == null) { continue; } String key = getPropertyName(prop); int slot = _hashCode(key); int ix = (slot<<1); // primary slot not free? if (hashed[ix] != null) { // secondary? ix = (hashSize + (slot >> 1)) << 1; if (hashed[ix] != null) { // ok, spill over. ix = ((hashSize + (hashSize >> 1) ) << 1) + spillCount; spillCount += 2; if (ix >= hashed.length) { hashed = Arrays.copyOf(hashed, hashed.length + 4); } } } hashed[ix] = key; hashed[ix+1] = prop; // and aliases } _hashArea = hashed; _spillCount = spillCount; } private final static int findSize(int size) { if (size <= 5) { return 8; } if (size <= 12) { return 16; } int needed = size + (size >> 2); // at most 80% full int result = 32; while (result < needed) { result += result; } return result; }
Since:2.6
/** * @since 2.6 */
public static BeanPropertyMap construct(Collection<SettableBeanProperty> props, boolean caseInsensitive, Map<String,List<PropertyName>> aliasMapping) { return new BeanPropertyMap(caseInsensitive, props, aliasMapping); } @Deprecated // since 2.9 public static BeanPropertyMap construct(Collection<SettableBeanProperty> props, boolean caseInsensitive) { return construct(props, caseInsensitive, Collections.<String,List<PropertyName>>emptyMap()); }
Fluent copy method that creates a new instance that is a copy of this instance except for one additional property that is passed as the argument. Note that method does not modify this instance but constructs and returns a new one.
/** * Fluent copy method that creates a new instance that is a copy * of this instance except for one additional property that is * passed as the argument. * Note that method does not modify this instance but constructs * and returns a new one. */
public BeanPropertyMap withProperty(SettableBeanProperty newProp) { // First: may be able to just replace? String key = getPropertyName(newProp); for (int i = 1, end = _hashArea.length; i < end; i += 2) { SettableBeanProperty prop = (SettableBeanProperty) _hashArea[i]; if ((prop != null) && prop.getName().equals(key)) { return new BeanPropertyMap(this, newProp, i, _findFromOrdered(prop)); } } // If not, append final int slot = _hashCode(key); return new BeanPropertyMap(this, newProp, key, slot); } public BeanPropertyMap assignIndexes() { // order is arbitrary, but stable: int index = 0; for (int i = 1, end = _hashArea.length; i < end; i += 2) { SettableBeanProperty prop = (SettableBeanProperty) _hashArea[i]; if (prop != null) { prop.assignIndex(index++); } } return this; }
Mutant factory method for constructing a map where all entries use given prefix
/** * Mutant factory method for constructing a map where all entries use given * prefix */
public BeanPropertyMap renameAll(NameTransformer transformer) { if (transformer == null || (transformer == NameTransformer.NOP)) { return this; } // Try to retain insertion ordering as well final int len = _propsInOrder.length; ArrayList<SettableBeanProperty> newProps = new ArrayList<SettableBeanProperty>(len); for (int i = 0; i < len; ++i) { SettableBeanProperty prop = _propsInOrder[i]; // What to do with holes? For now, retain if (prop == null) { newProps.add(prop); continue; } newProps.add(_rename(prop, transformer)); } // should we try to re-index? Ordering probably changed but caller probably doesn't want changes... // 26-Feb-2017, tatu: Probably SHOULD handle renaming wrt Aliases? return new BeanPropertyMap(_caseInsensitive, newProps, _aliasDefs); } /* /********************************************************** /* Public API, mutators /********************************************************** */
Mutant factory method that will use this instance as the base, and construct an instance that is otherwise same except for excluding properties with specified names.
Since:2.8
/** * Mutant factory method that will use this instance as the base, and * construct an instance that is otherwise same except for excluding * properties with specified names. * * @since 2.8 */
public BeanPropertyMap withoutProperties(Collection<String> toExclude) { if (toExclude.isEmpty()) { return this; } final int len = _propsInOrder.length; ArrayList<SettableBeanProperty> newProps = new ArrayList<SettableBeanProperty>(len); for (int i = 0; i < len; ++i) { SettableBeanProperty prop = _propsInOrder[i]; // 01-May-2015, tatu: Not 100% sure if existing `null`s should be retained; // or, if entries to ignore should be retained as nulls. For now just // prune them out if (prop != null) { // may contain holes, too, check. if (!toExclude.contains(prop.getName())) { newProps.add(prop); } } } // should we try to re-index? Apparently no need return new BeanPropertyMap(_caseInsensitive, newProps, _aliasDefs); } @Deprecated // in 2.9.4 -- must call method that takes old and new property to avoid mismatch public void replace(SettableBeanProperty newProp) { String key = getPropertyName(newProp); int ix = _findIndexInHash(key); if (ix < 0) { throw new NoSuchElementException("No entry '"+key+"' found, can't replace"); } SettableBeanProperty prop = (SettableBeanProperty) _hashArea[ix]; _hashArea[ix] = newProp; // also, replace in in-order _propsInOrder[_findFromOrdered(prop)] = newProp; }
Specialized method that can be used to replace an existing entry (note: entry MUST exist; otherwise exception is thrown) with specified replacement.
Since:2.9.4
/** * Specialized method that can be used to replace an existing entry * (note: entry MUST exist; otherwise exception is thrown) with * specified replacement. * * @since 2.9.4 */
public void replace(SettableBeanProperty origProp, SettableBeanProperty newProp) { int i = 1; int end = _hashArea.length; for (;; i += 2) { if (i > end) { throw new NoSuchElementException("No entry '"+origProp.getName()+"' found, can't replace"); } if (_hashArea[i] == origProp) { _hashArea[i] = newProp; break; } } _propsInOrder[_findFromOrdered(origProp)] = newProp; }
Specialized method for removing specified existing entry. NOTE: entry MUST exist, otherwise an exception is thrown.
/** * Specialized method for removing specified existing entry. * NOTE: entry MUST exist, otherwise an exception is thrown. */
public void remove(SettableBeanProperty propToRm) { ArrayList<SettableBeanProperty> props = new ArrayList<SettableBeanProperty>(_size); String key = getPropertyName(propToRm); boolean found = false; for (int i = 1, end = _hashArea.length; i < end; i += 2) { SettableBeanProperty prop = (SettableBeanProperty) _hashArea[i]; if (prop == null) { continue; } if (!found) { // 09-Jan-2017, tatu: Important: must check name slot and NOT property name, // as only former is lower-case in case-insensitive case found = key.equals(_hashArea[i-1]); if (found) { // need to leave a hole here _propsInOrder[_findFromOrdered(prop)] = null; continue; } } props.add(prop); } if (!found) { throw new NoSuchElementException("No entry '"+propToRm.getName()+"' found, can't remove"); } init(props); } /* /********************************************************** /* Public API, simple accessors /********************************************************** */ public int size() { return _size; }
Since:2.9
/** * @since 2.9 */
public boolean isCaseInsensitive() { return _caseInsensitive; }
Since:2.9
/** * @since 2.9 */
public boolean hasAliases() { return !_aliasDefs.isEmpty(); }
Accessor for traversing over all contained properties.
/** * Accessor for traversing over all contained properties. */
@Override public Iterator<SettableBeanProperty> iterator() { return _properties().iterator(); } private List<SettableBeanProperty> _properties() { ArrayList<SettableBeanProperty> p = new ArrayList<SettableBeanProperty>(_size); for (int i = 1, end = _hashArea.length; i < end; i += 2) { SettableBeanProperty prop = (SettableBeanProperty) _hashArea[i]; if (prop != null) { p.add(prop); } } return p; }
Method that will re-create initial insertion-ordering of properties contained in this map. Note that if properties have been removed, array may contain nulls; otherwise it should be consecutive.
Since:2.1
/** * Method that will re-create initial insertion-ordering of * properties contained in this map. Note that if properties * have been removed, array may contain nulls; otherwise * it should be consecutive. * * @since 2.1 */
public SettableBeanProperty[] getPropertiesInInsertionOrder() { return _propsInOrder; } // Confining this case insensitivity to this function (and the find method) in case we want to // apply a particular locale to the lower case function. For now, using the default. protected final String getPropertyName(SettableBeanProperty prop) { return _caseInsensitive ? prop.getName().toLowerCase() : prop.getName(); } /* /********************************************************** /* Public API, property lookup /********************************************************** */
Since:2.3
/** * @since 2.3 */
public SettableBeanProperty find(int index) { // note: will scan the whole area, including primary, secondary and // possible spill-area for (int i = 1, end = _hashArea.length; i < end; i += 2) { SettableBeanProperty prop = (SettableBeanProperty) _hashArea[i]; if ((prop != null) && (index == prop.getPropertyIndex())) { return prop; } } return null; } public SettableBeanProperty find(String key) { if (key == null) { throw new IllegalArgumentException("Cannot pass null property name"); } if (_caseInsensitive) { key = key.toLowerCase(); } // inlined `_hashCode(key)` int slot = key.hashCode() & _hashMask; // int h = key.hashCode(); // int slot = (h + (h >> 13)) & _hashMask; int ix = (slot<<1); Object match = _hashArea[ix]; if ((match == key) || key.equals(match)) { return (SettableBeanProperty) _hashArea[ix+1]; } return _find2(key, slot, match); } private final SettableBeanProperty _find2(String key, int slot, Object match) { if (match == null) { // 26-Feb-2017, tatu: Need to consider aliases return _findWithAlias(_aliasMapping.get(key)); } // no? secondary? int hashSize = _hashMask+1; int ix = hashSize + (slot>>1) << 1; match = _hashArea[ix]; if (key.equals(match)) { return (SettableBeanProperty) _hashArea[ix+1]; } if (match != null) { // _findFromSpill(...) int i = (hashSize + (hashSize>>1)) << 1; for (int end = i + _spillCount; i < end; i += 2) { match = _hashArea[i]; if ((match == key) || key.equals(match)) { return (SettableBeanProperty) _hashArea[i+1]; } } } // 26-Feb-2017, tatu: Need to consider aliases return _findWithAlias(_aliasMapping.get(key)); } private SettableBeanProperty _findWithAlias(String keyFromAlias) { if (keyFromAlias == null) { return null; } // NOTE: need to inline much of handling do avoid cyclic calls via alias // first, inlined main `find(String)` int slot = _hashCode(keyFromAlias); int ix = (slot<<1); Object match = _hashArea[ix]; if (keyFromAlias.equals(match)) { return (SettableBeanProperty) _hashArea[ix+1]; } if (match == null) { return null; } return _find2ViaAlias(keyFromAlias, slot, match); } private SettableBeanProperty _find2ViaAlias(String key, int slot, Object match) { // no? secondary? int hashSize = _hashMask+1; int ix = hashSize + (slot>>1) << 1; match = _hashArea[ix]; if (key.equals(match)) { return (SettableBeanProperty) _hashArea[ix+1]; } if (match != null) { // _findFromSpill(...) int i = (hashSize + (hashSize>>1)) << 1; for (int end = i + _spillCount; i < end; i += 2) { match = _hashArea[i]; if ((match == key) || key.equals(match)) { return (SettableBeanProperty) _hashArea[i+1]; } } } return null; } /* /********************************************************** /* Public API, deserialization support /********************************************************** */
Convenience method that tries to find property with given name, and if it is found, call SettableBeanProperty.deserializeAndSet on it, and return true; or, if not found, return false. Note, too, that if deserialization is attempted, possible exceptions are wrapped if and as necessary, so caller need not handle those.
Since:2.5
/** * Convenience method that tries to find property with given name, and * if it is found, call {@link SettableBeanProperty#deserializeAndSet} * on it, and return true; or, if not found, return false. * Note, too, that if deserialization is attempted, possible exceptions * are wrapped if and as necessary, so caller need not handle those. * * @since 2.5 */
public boolean findDeserializeAndSet(JsonParser p, DeserializationContext ctxt, Object bean, String key) throws IOException { final SettableBeanProperty prop = find(key); if (prop == null) { return false; } try { prop.deserializeAndSet(p, ctxt, bean); } catch (Exception e) { wrapAndThrow(e, bean, key, ctxt); } return true; } /* /********************************************************** /* Std method overrides /********************************************************** */ @Override public String toString() { StringBuilder sb = new StringBuilder(); sb.append("Properties=["); int count = 0; Iterator<SettableBeanProperty> it = iterator(); while (it.hasNext()) { SettableBeanProperty prop = it.next(); if (count++ > 0) { sb.append(", "); } sb.append(prop.getName()); sb.append('('); sb.append(prop.getType()); sb.append(')'); } sb.append(']'); if (!_aliasDefs.isEmpty()) { sb.append("(aliases: "); sb.append(_aliasDefs); sb.append(")"); } return sb.toString(); } /* /********************************************************** /* Helper methods /********************************************************** */ protected SettableBeanProperty _rename(SettableBeanProperty prop, NameTransformer xf) { if (prop == null) { return prop; } String newName = xf.transform(prop.getName()); prop = prop.withSimpleName(newName); JsonDeserializer<?> deser = prop.getValueDeserializer(); if (deser != null) { @SuppressWarnings("unchecked") JsonDeserializer<Object> newDeser = (JsonDeserializer<Object>) deser.unwrappingDeserializer(xf); if (newDeser != deser) { prop = prop.withValueDeserializer(newDeser); } } return prop; } protected void wrapAndThrow(Throwable t, Object bean, String fieldName, DeserializationContext ctxt) throws IOException { // inlined 'throwOrReturnThrowable' while (t instanceof InvocationTargetException && t.getCause() != null) { t = t.getCause(); } // Errors to be passed as is ClassUtil.throwIfError(t); // StackOverflowErrors are tricky ones; need to be careful... boolean wrap = (ctxt == null) || ctxt.isEnabled(DeserializationFeature.WRAP_EXCEPTIONS); // Ditto for IOExceptions; except we may want to wrap JSON exceptions if (t instanceof IOException) { if (!wrap || !(t instanceof JsonProcessingException)) { throw (IOException) t; } } else if (!wrap) { // allow disabling wrapping for unchecked exceptions ClassUtil.throwIfRTE(t); } throw JsonMappingException.wrapWithPath(t, bean, fieldName); }
Helper method used to find exact location of a property with name given exactly, not subject to case changes, within hash area. Expectation is that such property SHOULD exist, although no exception is thrown.
Since:2.7
/** * Helper method used to find exact location of a property with name * given exactly, not subject to case changes, within hash area. * Expectation is that such property SHOULD exist, although no * exception is thrown. * * @since 2.7 */
private final int _findIndexInHash(String key) { final int slot = _hashCode(key); int ix = (slot<<1); // primary match? if (key.equals(_hashArea[ix])) { return ix+1; } // no? secondary? int hashSize = _hashMask+1; ix = hashSize + (slot>>1) << 1; if (key.equals(_hashArea[ix])) { return ix+1; } // perhaps spill then int i = (hashSize + (hashSize>>1)) << 1; for (int end = i + _spillCount; i < end; i += 2) { if (key.equals(_hashArea[i])) { return i+1; } } return -1; } private final int _findFromOrdered(SettableBeanProperty prop) { for (int i = 0, end = _propsInOrder.length; i < end; ++i) { if (_propsInOrder[i] == prop) { return i; } } throw new IllegalStateException("Illegal state: property '"+prop.getName()+"' missing from _propsInOrder"); } // Offlined version for convenience if we want to change hashing scheme private final int _hashCode(String key) { // This method produces better hash, fewer collisions... yet for some // reason produces slightly worse performance. Very strange. // 05-Aug-2015, tatu: ... still true? /* int h = key.hashCode(); return (h + (h >> 13)) & _hashMask; */ return key.hashCode() & _hashMask; } // @since 2.9 private Map<String,String> _buildAliasMapping(Map<String,List<PropertyName>> defs) { if ((defs == null) || defs.isEmpty()) { return Collections.emptyMap(); } Map<String,String> aliases = new HashMap<>(); for (Map.Entry<String,List<PropertyName>> entry : defs.entrySet()) { String key = entry.getKey(); if (_caseInsensitive) { key = key.toLowerCase(); } for (PropertyName pn : entry.getValue()) { String mapped = pn.getSimpleName(); if (_caseInsensitive) { mapped = mapped.toLowerCase(); } aliases.put(mapped, key); } } return aliases; } }