记录一次源码扩展案列——FastJson自定义反序列化ValueMutator
2020-12-26 08:28
标签:替换 ref conf OLE ++ end 下载 system 关注
背景:曾经遇到一个很麻烦的事情,就是一个json串中有很多占位符,需要替换成特定文案。如果将json转换成对象后,在一个一个属性去转换的话就出出现很多冗余代码,不美观也不是很实用。 而且也不能提前在json串中替换,因为替换的文案会因为某些变量发生改变。就比如国际化,在中文的时候应该是"你好",而在英文的时候要出现"Hello"。 所以我想到一个方法,为什么不能再json反序列化的时候,把这些都做好呢? 以下的代码介绍的是,我自己扩展的一点点fastjson代码,增加了在反序列化的时候可以对所有的值进行修改的方案。 注意:这个方案会对fastjson反序列化的速度有一定的影响,我只是用来做配置的反序列化,完成后将反序列化的东西缓存起来使用。 使用方式有两种 一种是直接通过 @JsonDeserializer 注解的valueMutators属性注入这种方式有个缺陷,你的修改器必须有无参构造函数的 第二种方式是通过直接创建的方式,使用反序列化工具,这种方式支持有参构造函数。 下面先展示一下使用效果,测试代码如下: 运行效果:
下面是测试模型代码: 自定义的反序列化值修改器: 一些工具类和静态资源类: 下面给出的是扩展的关键代码。 首先是自定义解析配置类,这个类是核心。这个类继承了 com.alibaba.fastjson.parser.ParserConfig 类。覆写了其两个核心方法。 方法一: createFieldDeserializer(ParserConfig mapping, JavaBeanInfo beanInfo, FieldInfo fieldInfo) 创建一个属性反序列化处理类 该方法的修改,是将源码中的 ArrayListTypeFieldDeserializer 替换成 我们自定义的 CustomizeArrayListTypeFieldDeserializer 处理器。 将源码中的 DefaultFieldDeserializer 替换成 我们自定义的 CustomizeDefaultFieldDeserializer 处理器 方法二: createJavaBeanDeserializer(Class> clazz, Type type) 创建一个 JavaBean 反序列化处理器 新增判断逻辑,如果要反序列化的类上存在 @JsonDeserializer 标识注解,返回包含自定义配置类的 JavaBeanDeserializer。 CustomizeDefaultFieldDeserializer 类继承了 DefaultFieldDeserializer 类在构造方法中新增了参数 valueMutators(值修改器数组) 并在 public void setValue(Object object, Object value) 方法中新增了逻辑如果值修改器数组中存在值修改器,就遍历所有的修改器, 依次调用修改器的 process方法修改值。 类CustomizeArrayListTypeFieldDeserializer 和 类CustomizeDefaultFieldDeserializer 改动类似。 下面是值修改器接口定义: 反序列化标识注解,只有用这个注解注释的类才会执行拓展的方法。 强化的JSON序列化工具类: 以上代码都可以在我的git中下载:https://github.com/RaidenXin/fastjson-deserializer.git 创作不易,如果转载请注明出处,小编在此感谢各位看官。 如果觉得有用,请看官们点个赞,谢谢。 如果有想学Redis的可以关注我的Redis文章系列: 记录一次源码扩展案列——FastJson自定义反序列化ValueMutator 标签:替换 ref conf OLE ++ end 下载 system 关注 原文地址:https://www.cnblogs.com/Raiden-xin/p/13817754.html@JsonDeserializer(valueMutators = {CoustomizeValueMutator.class})
@Getter
@Setter
public class User {
private String name;
...
}
CoustomizeValueMutator zhCoustomizeValueMutator = new CoustomizeValueMutator(zh);
User user = CustomizeJSON.parseObject(userStr, User.class, zhCoustomizeValueMutator);
import com.alibaba.fastjson.parser.deserializer.CustomizeJSON;
import com.raiden.model.*;
import org.junit.jupiter.api.Test;
import java.util.*;
/**
* @创建人:Raiden
* @Descriotion:
* @Date:Created in 22:39 2020/1/28
* @Modified By:
*/
public class AppTest {
@Test
public void testFastJosn() throws Throwable {
String userStr = "{\n" +
"\t\"id\":\"I18nKey:20200411001\",\n" +
"\t\"a\":\"I18nKey:张三\",\n" +
"\t\"student\":\"I18nKey:高三三班\",\n" +
"\t\"contents\":[\"I18nKey:1\",\"I18nKey:2\"]\n" +
"}";
Map
import com.alibaba.fastjson.parser.deserializer.JsonDeserializer;
import com.raiden.CoustomizeValueMutator;
import lombok.Getter;
import lombok.Setter;
import java.util.List;
/**
* @创建人:Raiden
* @Descriotion:
* @Date:Created in 23:56 2020/4/17
* @Modified By:
*/
@JsonDeserializer
@Getter
@Setter
public class Administration {
private List
import com.alibaba.fastjson.parser.deserializer.JsonDeserializer;
import lombok.Getter;
import lombok.Setter;
import java.util.List;
/**
* @创建人:Raiden
* @Descriotion:
* @Date:Created in 15:53 2020/3/21
* @Modified By:
*/
@JsonDeserializer
@Getter
@Setter
public class User {
private String name;
private String id;
private String student;
private List
import com.alibaba.fastjson.parser.deserializer.DeserializerValueMutator;
import java.lang.annotation.Annotation;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
/**
* @创建人:Raiden
* @Descriotion:
* @Date:Created in 22:15 2020/5/1
* @Modified By:
*/
public class CoustomizeValueMutator implements DeserializerValueMutator {
private Map
/**
* @创建人:Raiden
* @Descriotion:
* @Date:Created in 23:00 2020/4/17
* @Modified By:
*/
public class CustomizeStaticConfig {
public static final String I18N_KEY = "I18nKey:";
}
import org.apache.commons.lang3.StringUtils;
import java.util.Map;
/**
* @创建人:Raiden
* @Descriotion:
* @Date:Created in 0:15 2020/4/18
* @Modified By:
*/
public final class DeserializerUtils {
public static final Object deserializer(Object value, Map
import com.alibaba.fastjson.annotation.JSONField;
import com.alibaba.fastjson.parser.ParserConfig;
import com.alibaba.fastjson.util.FieldInfo;
import com.alibaba.fastjson.util.JavaBeanInfo;
import java.lang.reflect.Type;
import java.util.ArrayList;
import java.util.List;
/**
* @创建人:Raiden
* @Descriotion:
* @Date:Created in 21:52 2020/4/17
* @Modified By: 自定义fastjson 解析配置类 这个类是核心
*/
public class CustomizeParserConfig extends ParserConfig {
/**
* 值修改器数组 可以将类修改器放入其中使用
*/
private DeserializerValueMutator[] valueMutators;
public CustomizeParserConfig(){
}
/**
* 有参构造方法 可以通过该方法 将类修改器放入其中
* @param valueMutators
*/
public CustomizeParserConfig(DeserializerValueMutator... valueMutators){
super();
this.valueMutators = valueMutators;
}
/**
* 创建一个属性反序列化处理类
* @param mapping
* @param beanInfo
* @param fieldInfo
* @return
*/
@Override
public FieldDeserializer createFieldDeserializer(ParserConfig mapping, //
JavaBeanInfo beanInfo, //
FieldInfo fieldInfo) {
//获取要反序列化的model 的class
Class> clazz = beanInfo.clazz;
//获取要反序列化属性的 class
Class> fieldClass = fieldInfo.fieldClass;
Class> deserializeUsing = null;
JSONField annotation = fieldInfo.getAnnotation();
if (annotation != null) {
deserializeUsing = annotation.deserializeUsing();
if (deserializeUsing == Void.class) {
deserializeUsing = null;
}
}
if (deserializeUsing == null && (fieldClass == List.class || fieldClass == ArrayList.class)) {
//将源码中的 ArrayListTypeFieldDeserializer 替换成 我们自定义的 CustomizeArrayListTypeFieldDeserializer 处理器
return new CustomizeArrayListTypeFieldDeserializer(clazz, fieldInfo, valueMutators);
}
//将源码中的 DefaultFieldDeserializer 替换成 我们自定义的 CustomizeDefaultFieldDeserializer 处理器
return new CustomizeDefaultFieldDeserializer(mapping, clazz, fieldInfo, valueMutators);
}
/**
* 创建一个 javaBean 反序列化处理器
* @param clazz
* @param type
* @return
*/
@Override
public ObjectDeserializer createJavaBeanDeserializer(Class> clazz, Type type) {
//获取要反序列化类上的标识注解
JsonDeserializer jsonDeserializer = clazz.getAnnotation(JsonDeserializer.class);
//如果不存在就走原逻辑
if (jsonDeserializer != null){
//获取注解中的反序列化值处理器
Class extends DeserializerValueMutator>[] classes = jsonDeserializer.valueMutators();
if (classes != null && classes.length > 0){
DeserializerValueMutator[] mutators = new DeserializerValueMutator[classes.length];
int size = 0;
for (Class extends DeserializerValueMutator> c : classes) {
try {
DeserializerValueMutator mutator = c.newInstance();
mutators[size] = mutator;
size++;
} catch (Exception e) {
//如果创建失败了就忽略掉这次错误
}
}
if (size > 0){
//判断原来是否有值 如果有 就合并成一组
if (valueMutators != null){
DeserializerValueMutator[] newValueMutators = new DeserializerValueMutator[size + valueMutators.length];
System.arraycopy(valueMutators, 0, newValueMutators, 0, valueMutators.length);
System.arraycopy(mutators, 0, newValueMutators, valueMutators.length, size);
this.valueMutators = newValueMutators;
}else {
this.valueMutators = new DeserializerValueMutator[size];
System.arraycopy(mutators, 0, valueMutators, 0, size);
}
}
}
if (valueMutators != null){
return new JavaBeanDeserializer(this, clazz);
}
}
return super.createJavaBeanDeserializer(clazz, type);
}
}
import com.alibaba.fastjson.JSONException;
import com.alibaba.fastjson.parser.ParserConfig;
import com.alibaba.fastjson.util.FieldInfo;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.Collection;
import java.util.Collections;
import java.util.Map;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicLong;
/**
* @创建人:Raiden
* @Descriotion:
* @Date:Created in 0:13 2020/4/18
* @Modified By: 替代fastjson中 对象反序列化处理类
*/
public class CustomizeDefaultFieldDeserializer extends DefaultFieldDeserializer {
private DeserializerValueMutator[] valueMutators;
public CustomizeDefaultFieldDeserializer(ParserConfig config, Class> clazz, FieldInfo fieldInfo,DeserializerValueMutator[] valueMutators) {
super(config, clazz, fieldInfo);
this.valueMutators = valueMutators;
}
public void setValue(Object object, Object value) {
if (value == null //
&& fieldInfo.fieldClass.isPrimitive()) {
return;
} else if (fieldInfo.fieldClass == String.class
&& fieldInfo.format != null
&& fieldInfo.format.equals("trim")){
value = ((String) value).trim();
}
try {
/**
* 如果值修改器数组中存在值修改器实例,就遍历该数组,依次调用所有的修改器的 process方法
*/
if (valueMutators != null && valueMutators.length > 0){
for (DeserializerValueMutator mutator : valueMutators){
value = mutator.process(object,fieldInfo.field.getAnnotations(), fieldInfo.name, value);
}
}
Method method = fieldInfo.method;
if (method != null) {
if (fieldInfo.getOnly) {
if (fieldInfo.fieldClass == AtomicInteger.class) {
AtomicInteger atomic = (AtomicInteger) method.invoke(object);
if (atomic != null) {
atomic.set(((AtomicInteger) value).get());
}
} else if (fieldInfo.fieldClass == AtomicLong.class) {
AtomicLong atomic = (AtomicLong) method.invoke(object);
if (atomic != null) {
atomic.set(((AtomicLong) value).get());
}
} else if (fieldInfo.fieldClass == AtomicBoolean.class) {
AtomicBoolean atomic = (AtomicBoolean) method.invoke(object);
if (atomic != null) {
atomic.set(((AtomicBoolean) value).get());
}
} else if (Map.class.isAssignableFrom(method.getReturnType())) {
Map map = (Map) method.invoke(object);
if (map != null) {
if (map == Collections.emptyMap()
|| map.getClass().getName().startsWith("java.util.Collections$Unmodifiable")) {
// skip
return;
}
map.putAll((Map) value);
}
} else {
Collection collection = (Collection) method.invoke(object);
if (collection != null && value != null) {
if (collection == Collections.emptySet()
|| collection == Collections.emptyList()
|| collection.getClass().getName().startsWith("java.util.Collections$Unmodifiable")) {
// skip
return;
}
collection.clear();
collection.addAll((Collection) value);
}
}
} else {
method.invoke(object, value);
}
} else {
final Field field = fieldInfo.field;
if (fieldInfo.getOnly) {
if (fieldInfo.fieldClass == AtomicInteger.class) {
AtomicInteger atomic = (AtomicInteger) field.get(object);
if (atomic != null) {
atomic.set(((AtomicInteger) value).get());
}
} else if (fieldInfo.fieldClass == AtomicLong.class) {
AtomicLong atomic = (AtomicLong) field.get(object);
if (atomic != null) {
atomic.set(((AtomicLong) value).get());
}
} else if (fieldInfo.fieldClass == AtomicBoolean.class) {
AtomicBoolean atomic = (AtomicBoolean) field.get(object);
if (atomic != null) {
atomic.set(((AtomicBoolean) value).get());
}
} else if (Map.class.isAssignableFrom(fieldInfo.fieldClass)) {
Map map = (Map) field.get(object);
if (map != null) {
if (map == Collections.emptyMap()
|| map.getClass().getName().startsWith("java.util.Collections$Unmodifiable")) {
// skip
return;
}
map.putAll((Map) value);
}
} else {
Collection collection = (Collection) field.get(object);
if (collection != null && value != null) {
if (collection == Collections.emptySet()
|| collection == Collections.emptyList()
|| collection.getClass().getName().startsWith("java.util.Collections$Unmodifiable")) {
// skip
return;
}
collection.clear();
collection.addAll((Collection) value);
}
}
} else {
if (field != null) {
field.set(object, value);
}
}
}
} catch (Exception e) {
throw new JSONException("set property error, " + clazz.getName() + "#" + fieldInfo.name, e);
}
}
}
import com.alibaba.fastjson.JSONException;
import com.alibaba.fastjson.parser.ParserConfig;
import com.alibaba.fastjson.util.FieldInfo;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.Collection;
import java.util.Collections;
import java.util.Map;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicLong;
/**
* @创建人:Raiden
* @Descriotion:
* @Date:Created in 0:13 2020/4/18
* @Modified By: 替代fastjson中 对象反序列化处理类
*/
public class CustomizeDefaultFieldDeserializer extends DefaultFieldDeserializer {
private DeserializerValueMutator[] valueMutators;
public CustomizeDefaultFieldDeserializer(ParserConfig config, Class> clazz, FieldInfo fieldInfo,DeserializerValueMutator[] valueMutators) {
super(config, clazz, fieldInfo);
this.valueMutators = valueMutators;
}
public void setValue(Object object, Object value) {
if (value == null //
&& fieldInfo.fieldClass.isPrimitive()) {
return;
} else if (fieldInfo.fieldClass == String.class
&& fieldInfo.format != null
&& fieldInfo.format.equals("trim")){
value = ((String) value).trim();
}
try {
/**
* 如果值修改器数组中存在值修改器实例,就遍历该数组,依次调用所有的修改器的 process方法
*/
if (valueMutators != null && valueMutators.length > 0){
for (DeserializerValueMutator mutator : valueMutators){
value = mutator.process(object,fieldInfo.field.getAnnotations(), fieldInfo.name, value);
}
}
Method method = fieldInfo.method;
if (method != null) {
if (fieldInfo.getOnly) {
if (fieldInfo.fieldClass == AtomicInteger.class) {
AtomicInteger atomic = (AtomicInteger) method.invoke(object);
if (atomic != null) {
atomic.set(((AtomicInteger) value).get());
}
} else if (fieldInfo.fieldClass == AtomicLong.class) {
AtomicLong atomic = (AtomicLong) method.invoke(object);
if (atomic != null) {
atomic.set(((AtomicLong) value).get());
}
} else if (fieldInfo.fieldClass == AtomicBoolean.class) {
AtomicBoolean atomic = (AtomicBoolean) method.invoke(object);
if (atomic != null) {
atomic.set(((AtomicBoolean) value).get());
}
} else if (Map.class.isAssignableFrom(method.getReturnType())) {
Map map = (Map) method.invoke(object);
if (map != null) {
if (map == Collections.emptyMap()
|| map.getClass().getName().startsWith("java.util.Collections$Unmodifiable")) {
// skip
return;
}
map.putAll((Map) value);
}
} else {
Collection collection = (Collection) method.invoke(object);
if (collection != null && value != null) {
if (collection == Collections.emptySet()
|| collection == Collections.emptyList()
|| collection.getClass().getName().startsWith("java.util.Collections$Unmodifiable")) {
// skip
return;
}
collection.clear();
collection.addAll((Collection) value);
}
}
} else {
method.invoke(object, value);
}
} else {
final Field field = fieldInfo.field;
if (fieldInfo.getOnly) {
if (fieldInfo.fieldClass == AtomicInteger.class) {
AtomicInteger atomic = (AtomicInteger) field.get(object);
if (atomic != null) {
atomic.set(((AtomicInteger) value).get());
}
} else if (fieldInfo.fieldClass == AtomicLong.class) {
AtomicLong atomic = (AtomicLong) field.get(object);
if (atomic != null) {
atomic.set(((AtomicLong) value).get());
}
} else if (fieldInfo.fieldClass == AtomicBoolean.class) {
AtomicBoolean atomic = (AtomicBoolean) field.get(object);
if (atomic != null) {
atomic.set(((AtomicBoolean) value).get());
}
} else if (Map.class.isAssignableFrom(fieldInfo.fieldClass)) {
Map map = (Map) field.get(object);
if (map != null) {
if (map == Collections.emptyMap()
|| map.getClass().getName().startsWith("java.util.Collections$Unmodifiable")) {
// skip
return;
}
map.putAll((Map) value);
}
} else {
Collection collection = (Collection) field.get(object);
if (collection != null && value != null) {
if (collection == Collections.emptySet()
|| collection == Collections.emptyList()
|| collection.getClass().getName().startsWith("java.util.Collections$Unmodifiable")) {
// skip
return;
}
collection.clear();
collection.addAll((Collection) value);
}
}
} else {
if (field != null) {
field.set(object, value);
}
}
}
} catch (Exception e) {
throw new JSONException("set property error, " + clazz.getName() + "#" + fieldInfo.name, e);
}
}
}
import java.lang.annotation.Annotation;
/**
* @创建人:Raiden
* @Descriotion:
* @Date:Created in 22:01 2020/5/1
* @Modified By: 反序列化值修改器接口
*/
public interface DeserializerValueMutator {
Object process(Object object, Annotation[] annotations, String name, Object value);
}
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* @创建人:Raiden
* @Descriotion:
* @Date:Created in 22:25 2020/4/17
* @Modified By: 反序列化值修改标识注解
*/
@Retention(RetentionPolicy.RUNTIME)
@Target({ ElementType.TYPE })
public @interface JsonDeserializer {
/**
* 注意这里只能放无参构造函数的修改器 否则会创建失败
* @return
*/
Class extends DeserializerValueMutator>[] valueMutators() default {};
}
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.parser.Feature;
import java.lang.reflect.Type;
/**
* @创建人:Raiden
* @Descriotion:
* @Date:Created in 22:12 2020/5/1
* @Modified By: 反序列化工具类
*/
public final class CustomizeJSON {
public static
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文章标题:记录一次源码扩展案列——FastJson自定义反序列化ValueMutator
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