jodd.introspector.Fields Maven / Gradle / Ivy
// Copyright (c) 2003-present, Jodd Team (http://jodd.org)
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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package jodd.introspector;
import jodd.util.ClassUtil;
import java.lang.reflect.Field;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.Map;
/**
* Collection of {@link FieldDescriptor field descriptors}.
*/
public class Fields {
protected final ClassDescriptor classDescriptor;
protected final Map fieldsMap;
// cache
private FieldDescriptor[] allFields;
/**
* Creates new fields collection.
*/
public Fields(final ClassDescriptor classDescriptor) {
this.classDescriptor = classDescriptor;
this.fieldsMap = inspectFields();
}
/**
* Inspects fields and returns map of {@link FieldDescriptor field descriptors}.
*/
private Map inspectFields() {
if (classDescriptor.isSystemClass()) {
return emptyFields();
}
final boolean scanAccessible = classDescriptor.isScanAccessible();
final Class type = classDescriptor.getType();
final Field[] fields = scanAccessible ? ClassUtil.getAccessibleFields(type) : ClassUtil.getSupportedFields(type);
final HashMap map = new HashMap<>(fields.length);
for (final Field field : fields) {
final String fieldName = field.getName();
if (fieldName.equals("serialVersionUID")) {
continue;
}
map.put(fieldName, createFieldDescriptor(field));
}
return map;
}
/**
* Defines empty fields for special cases.
*/
private Map emptyFields() {
allFields = FieldDescriptor.EMPTY_ARRAY;
return Collections.emptyMap();
}
/**
* Creates new {@code FieldDescriptor}.
*/
protected FieldDescriptor createFieldDescriptor(final Field field) {
return new FieldDescriptor(classDescriptor, field);
}
// ---------------------------------------------------------------- get
/**
* Returns {@link FieldDescriptor field descriptor} for given field name
* or null if field does not exist.
*/
public FieldDescriptor getFieldDescriptor(final String name) {
return fieldsMap.get(name);
}
/**
* Returns all fields of this collection. Returns empty array
* if no fields exist. Initialized lazy.
*/
public FieldDescriptor[] getAllFieldDescriptors() {
if (allFields == null) {
FieldDescriptor[] allFields = new FieldDescriptor[fieldsMap.size()];
int index = 0;
for (FieldDescriptor fieldDescriptor : fieldsMap.values()) {
allFields[index] = fieldDescriptor;
index++;
}
Arrays.sort(allFields, Comparator.comparing(fd -> fd.getField().getName()));
this.allFields = allFields;
}
return allFields;
}
}