JSON树节点的增删查改

最近了解到使用json字符串存到数据库的一种存储方式,取出来的json字符串可以进行相应的节点操作

故借此机会练习下递归,完成对json节点操作对应的工具类。

介绍一下我使用的依赖

     <!-- fastjson -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.49</version>
        </dependency>

主要使用JSONObject和JSONArray的API进行相关操作,这里附上这两个类的代码

/*
 * Copyright 1999-2017 Alibaba Group.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.alibaba.fastjson;

import static com.alibaba.fastjson.util.TypeUtils.castToBigDecimal;
import static com.alibaba.fastjson.util.TypeUtils.castToBigInteger;
import static com.alibaba.fastjson.util.TypeUtils.castToBoolean;
import static com.alibaba.fastjson.util.TypeUtils.castToByte;
import static com.alibaba.fastjson.util.TypeUtils.castToBytes;
import static com.alibaba.fastjson.util.TypeUtils.castToDate;
import static com.alibaba.fastjson.util.TypeUtils.castToDouble;
import static com.alibaba.fastjson.util.TypeUtils.castToFloat;
import static com.alibaba.fastjson.util.TypeUtils.castToInt;
import static com.alibaba.fastjson.util.TypeUtils.castToLong;
import static com.alibaba.fastjson.util.TypeUtils.castToShort;
import static com.alibaba.fastjson.util.TypeUtils.castToSqlDate;
import static com.alibaba.fastjson.util.TypeUtils.castToTimestamp;

import java.io.*;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Type;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.Collection;
import java.util.Date;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Set;

import com.alibaba.fastjson.annotation.JSONField;
import com.alibaba.fastjson.parser.ParserConfig;
import com.alibaba.fastjson.util.TypeUtils;

/**
 * @author wenshao[szujobs@hotmail.com]
 */
public class JSONObject extends JSON implements Map<String, Object>, Cloneable, Serializable, InvocationHandler {

    private static final long         serialVersionUID         = 1L;
    private static final int          DEFAULT_INITIAL_CAPACITY = 16;

    private final Map<String, Object> map;

    public JSONObject(){
        this(DEFAULT_INITIAL_CAPACITY, false);
    }

    public JSONObject(Map<String, Object> map){
        if (map == null) {
            throw new IllegalArgumentException("map is null.");
        }
        this.map = map;
    }

    public JSONObject(boolean ordered){
        this(DEFAULT_INITIAL_CAPACITY, ordered);
    }

    public JSONObject(int initialCapacity){
        this(initialCapacity, false);
    }

    public JSONObject(int initialCapacity, boolean ordered){
        if (ordered) {
            map = new LinkedHashMap<String, Object>(initialCapacity);
        } else {
            map = new HashMap<String, Object>(initialCapacity);
        }
    }

    public int size() {
        return map.size();
    }

    public boolean isEmpty() {
        return map.isEmpty();
    }

    public boolean containsKey(Object key) {
        return map.containsKey(key);
    }

    public boolean containsValue(Object value) {
        return map.containsValue(value);
    }

    public Object get(Object key) {
        Object val = map.get(key);

        if (val == null && key instanceof Number) {
            val = map.get(key.toString());
        }

        return val;
    }

    public JSONObject getJSONObject(String key) {
        Object value = map.get(key);

        if (value instanceof JSONObject) {
            return (JSONObject) value;
        }

        if (value instanceof String) {
            return JSON.parseObject((String) value);
        }

        return (JSONObject) toJSON(value);
    }

    public JSONArray getJSONArray(String key) {
        Object value = map.get(key);

        if (value instanceof JSONArray) {
            return (JSONArray) value;
        }

        if (value instanceof String) {
            return (JSONArray) JSON.parse((String) value);
        }

        return (JSONArray) toJSON(value);
    }

    public <T> T getObject(String key, Class<T> clazz) {
        Object obj = map.get(key);
        return TypeUtils.castToJavaBean(obj, clazz);
    }

    public <T> T getObject(String key, Type type) {
        Object obj = map.get(key);
        return TypeUtils.cast(obj, type, ParserConfig.getGlobalInstance());
    }

    public <T> T getObject(String key, TypeReference typeReference) {
        Object obj = map.get(key);
        if (typeReference == null) {
            return (T) obj;
        }
        return TypeUtils.cast(obj, typeReference.getType(), ParserConfig.getGlobalInstance());
    }

    public Boolean getBoolean(String key) {
        Object value = get(key);

        if (value == null) {
            return null;
        }

        return castToBoolean(value);
    }

    public byte[] getBytes(String key) {
        Object value = get(key);

        if (value == null) {
            return null;
        }

        return castToBytes(value);
    }

    public boolean getBooleanValue(String key) {
        Object value = get(key);

        Boolean booleanVal = castToBoolean(value);
        if (booleanVal == null) {
            return false;
        }

        return booleanVal.booleanValue();
    }

    public Byte getByte(String key) {
        Object value = get(key);

        return castToByte(value);
    }

    public byte getByteValue(String key) {
        Object value = get(key);

        Byte byteVal = castToByte(value);
        if (byteVal == null) {
            return 0;
        }

        return byteVal.byteValue();
    }

    public Short getShort(String key) {
        Object value = get(key);

        return castToShort(value);
    }

    public short getShortValue(String key) {
        Object value = get(key);

        Short shortVal = castToShort(value);
        if (shortVal == null) {
            return 0;
        }

        return shortVal.shortValue();
    }

    public Integer getInteger(String key) {
        Object value = get(key);

        return castToInt(value);
    }

    public int getIntValue(String key) {
        Object value = get(key);

        Integer intVal = castToInt(value);
        if (intVal == null) {
            return 0;
        }

        return intVal.intValue();
    }

    public Long getLong(String key) {
        Object value = get(key);

        return castToLong(value);
    }

    public long getLongValue(String key) {
        Object value = get(key);

        Long longVal = castToLong(value);
        if (longVal == null) {
            return 0L;
        }

        return longVal.longValue();
    }

    public Float getFloat(String key) {
        Object value = get(key);

        return castToFloat(value);
    }

    public float getFloatValue(String key) {
        Object value = get(key);

        Float floatValue = castToFloat(value);
        if (floatValue == null) {
            return 0F;
        }

        return floatValue.floatValue();
    }

    public Double getDouble(String key) {
        Object value = get(key);

        return castToDouble(value);
    }

    public double getDoubleValue(String key) {
        Object value = get(key);

        Double doubleValue = castToDouble(value);
        if (doubleValue == null) {
            return 0D;
        }

        return doubleValue.doubleValue();
    }

    public BigDecimal getBigDecimal(String key) {
        Object value = get(key);

        return castToBigDecimal(value);
    }

    public BigInteger getBigInteger(String key) {
        Object value = get(key);

        return castToBigInteger(value);
    }

    public String getString(String key) {
        Object value = get(key);

        if (value == null) {
            return null;
        }

        return value.toString();
    }

    public Date getDate(String key) {
        Object value = get(key);

        return castToDate(value);
    }

    public java.sql.Date getSqlDate(String key) {
        Object value = get(key);

        return castToSqlDate(value);
    }

    public java.sql.Timestamp getTimestamp(String key) {
        Object value = get(key);

        return castToTimestamp(value);
    }
    
    public Object put(String key, Object value) {
        return map.put(key, value);
    }
    
    public JSONObject fluentPut(String key, Object value) {
        map.put(key, value);
        return this;
    }

    public void putAll(Map<? extends String, ? extends Object> m) {
        map.putAll(m);
    }

    public JSONObject fluentPutAll(Map<? extends String, ? extends Object> m) {
        map.putAll(m);
        return this;
    }

    public void clear() {
        map.clear();
    }

    public JSONObject fluentClear() {
        map.clear();
        return this;
    }

    public Object remove(Object key) {
        return map.remove(key);
    }

    public JSONObject fluentRemove(Object key) {
        map.remove(key);
        return this;
    }

    public Set<String> keySet() {
        return map.keySet();
    }

    public Collection<Object> values() {
        return map.values();
    }

    public Set<Map.Entry<String, Object>> entrySet() {
        return map.entrySet();
    }

    @Override
    public Object clone() {
        return new JSONObject(map instanceof LinkedHashMap //
                              ? new LinkedHashMap<String, Object>(map) //
                                  : new HashMap<String, Object>(map)
                                  );
    }

    public boolean equals(Object obj) {
        return this.map.equals(obj);
    }

    public int hashCode() {
        return this.map.hashCode();
    }

    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
        Class<?>[] parameterTypes = method.getParameterTypes();
        if (parameterTypes.length == 1) {
            if (method.getName().equals("equals")) {
                return this.equals(args[0]);
            }
            
            Class<?> returnType = method.getReturnType();
            if (returnType != void.class) {
                throw new JSONException("illegal setter");
            }

            String name = null;
            JSONField annotation = method.getAnnotation(JSONField.class);
            if (annotation != null) {
                if (annotation.name().length() != 0) {
                    name = annotation.name();
                }
            }

            if (name == null) {
                name = method.getName();
                
                if (!name.startsWith("set")) {
                    throw new JSONException("illegal setter");
                }

                name = name.substring(3);
                if (name.length() == 0) {
                    throw new JSONException("illegal setter");
                }
                name = Character.toLowerCase(name.charAt(0)) + name.substring(1);
            }

            map.put(name, args[0]);
            return null;
        }

        if (parameterTypes.length == 0) {
            Class<?> returnType = method.getReturnType();
            if (returnType == void.class) {
                throw new JSONException("illegal getter");
            }

            String name = null;
            JSONField annotation = method.getAnnotation(JSONField.class);
            if (annotation != null) {
                if (annotation.name().length() != 0) {
                    name = annotation.name();
                }
            }

            if (name == null) {
                name = method.getName();
                if (name.startsWith("get")) {
                    name = name.substring(3);
                    if (name.length() == 0) {
                        throw new JSONException("illegal getter");
                    }
                    name = Character.toLowerCase(name.charAt(0)) + name.substring(1);
                } else if (name.startsWith("is")) {
                    name = name.substring(2);
                    if (name.length() == 0) {
                        throw new JSONException("illegal getter");
                    }
                    name = Character.toLowerCase(name.charAt(0)) + name.substring(1);
                } else if (name.startsWith("hashCode")) {
                    return this.hashCode();
                } else if (name.startsWith("toString")) {
                    return this.toString();
                } else {
                    throw new JSONException("illegal getter");
                }
            }
            
            Object value = map.get(name);
            return TypeUtils.cast(value, method.getGenericReturnType(), ParserConfig.getGlobalInstance());
        }

        throw new UnsupportedOperationException(method.toGenericString());
    }

    public Map<String, Object> getInnerMap() {
        return this.map;
    }



    private void readObject(final java.io.ObjectInputStream in) throws IOException, ClassNotFoundException {
        SecureObjectInputStream.ensureFields();
        if (SecureObjectInputStream.fields != null && !SecureObjectInputStream.fields_error) {
            ObjectInputStream secIn = new SecureObjectInputStream(in);
            secIn.defaultReadObject();
            return;
        }

        in.defaultReadObject();
        for (Entry entry : map.entrySet()) {
            final Object key = entry.getKey();
            if (key != null) {
                ParserConfig.global.checkAutoType(key.getClass().getName(), null);
            }

            final Object value = entry.getValue();
            if (value != null) {
                ParserConfig.global.checkAutoType(value.getClass().getName(), null);
            }
        }
    }

    static class SecureObjectInputStream extends ObjectInputStream {
        static Field[] fields;
        static volatile boolean fields_error;

        static void ensureFields() {
            if (fields == null && !fields_error) {
                try {
                    final Field[] declaredFields = ObjectInputStream.class.getDeclaredFields();
                    String[] fieldnames = new String[]{"bin", "passHandle", "handles", "curContext"};
                    Field[] array = new Field[fieldnames.length];
                    for (int i = 0; i < fieldnames.length; i++) {
                        Field field = TypeUtils
                                .getField(ObjectInputStream.class
                                        , fieldnames[i]
                                        , declaredFields
                                );
                        field.setAccessible(true);
                        array[i] = field;
                    }
                    fields = array;
                } catch (Throwable error) {
                    fields_error = true;
                }
            }
        }

        public SecureObjectInputStream(ObjectInputStream in) throws IOException {
            super(in);
            try {
                for (int i = 0; i < fields.length; i++) {
                    final Field field = fields[i];
                    final Object value = field.get(in);
                    field.set(this, value);
                }
            } catch (IllegalAccessException e) {
                fields_error = true;
            }
        }

        protected Class<?> resolveClass(ObjectStreamClass desc)
        throws IOException, ClassNotFoundException {
            String name = desc.getName();
            ParserConfig.global.checkAutoType(name, null);
            return super.resolveClass(desc);
        }

        protected Class<?> resolveProxyClass(String[] interfaces)
        throws IOException, ClassNotFoundException {
            for (String interfacename : interfaces) {
                //检查是否处于黑名单
                ParserConfig.global.checkAutoType(interfacename, null);
            }
            return super.resolveProxyClass(interfaces);
        }

        //Hack:默认构造方法会调用这个方法,重写此方法使用反射还原部分关键属性
        protected void readStreamHeader() throws IOException, StreamCorruptedException {

        }
    }
}
JSONObject
/*
 * Copyright 1999-2017 Alibaba Group.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.alibaba.fastjson;

import static com.alibaba.fastjson.util.TypeUtils.castToBigDecimal;
import static com.alibaba.fastjson.util.TypeUtils.castToBigInteger;
import static com.alibaba.fastjson.util.TypeUtils.castToBoolean;
import static com.alibaba.fastjson.util.TypeUtils.castToByte;
import static com.alibaba.fastjson.util.TypeUtils.castToDate;
import static com.alibaba.fastjson.util.TypeUtils.castToDouble;
import static com.alibaba.fastjson.util.TypeUtils.castToFloat;
import static com.alibaba.fastjson.util.TypeUtils.castToInt;
import static com.alibaba.fastjson.util.TypeUtils.castToLong;
import static com.alibaba.fastjson.util.TypeUtils.castToShort;
import static com.alibaba.fastjson.util.TypeUtils.castToSqlDate;
import static com.alibaba.fastjson.util.TypeUtils.castToString;
import static com.alibaba.fastjson.util.TypeUtils.castToTimestamp;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.Serializable;
import java.lang.reflect.Type;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.*;

import com.alibaba.fastjson.parser.ParserConfig;
import com.alibaba.fastjson.parser.deserializer.ObjectDeserializer;
import com.alibaba.fastjson.util.TypeUtils;

/**
 * @author wenshao[szujobs@hotmail.com]
 */
public class JSONArray extends JSON implements List<Object>, Cloneable, RandomAccess, Serializable {

    private static final long  serialVersionUID = 1L;
    private final List<Object> list;
    protected transient Object relatedArray;
    protected transient Type   componentType;

    public JSONArray(){
        this.list = new ArrayList<Object>();
    }

    public JSONArray(List<Object> list){
        this.list = list;
    }

    public JSONArray(int initialCapacity){
        this.list = new ArrayList<Object>(initialCapacity);
    }

    /**
     * @since 1.1.16
     * @return
     */
    public Object getRelatedArray() {
        return relatedArray;
    }

    public void setRelatedArray(Object relatedArray) {
        this.relatedArray = relatedArray;
    }

    public Type getComponentType() {
        return componentType;
    }

    public void setComponentType(Type componentType) {
        this.componentType = componentType;
    }

    public int size() {
        return list.size();
    }

    public boolean isEmpty() {
        return list.isEmpty();
    }

    public boolean contains(Object o) {
        return list.contains(o);
    }

    public Iterator<Object> iterator() {
        return list.iterator();
    }

    public Object[] toArray() {
        return list.toArray();
    }

    public <T> T[] toArray(T[] a) {
        return list.toArray(a);
    }

    public boolean add(Object e) {
        return list.add(e);
    }

    public JSONArray fluentAdd(Object e) {
        list.add(e);
        return this;
    }

    public boolean remove(Object o) {
        return list.remove(o);
    }

    public JSONArray fluentRemove(Object o) {
        list.remove(o);
        return this;
    }

    public boolean containsAll(Collection<?> c) {
        return list.containsAll(c);
    }

    public boolean addAll(Collection<? extends Object> c) {
        return list.addAll(c);
    }

    public JSONArray fluentAddAll(Collection<? extends Object> c) {
        list.addAll(c);
        return this;
    }

    public boolean addAll(int index, Collection<? extends Object> c) {
        return list.addAll(index, c);
    }

    public JSONArray fluentAddAll(int index, Collection<? extends Object> c) {
        list.addAll(index, c);
        return this;
    }

    public boolean removeAll(Collection<?> c) {
        return list.removeAll(c);
    }

    public JSONArray fluentRemoveAll(Collection<?> c) {
        list.removeAll(c);
        return this;
    }

    public boolean retainAll(Collection<?> c) {
        return list.retainAll(c);
    }

    public JSONArray fluentRetainAll(Collection<?> c) {
        list.retainAll(c);
        return this;
    }

    public void clear() {
        list.clear();
    }

    public JSONArray fluentClear() {
        list.clear();
        return this;
    }

    public Object set(int index, Object element) {
        if (index == -1) {
            list.add(element);
            return null;
        }
        
        if (list.size() <= index) {
            for (int i = list.size(); i < index; ++i) {
                list.add(null);
            }
            list.add(element);
            return null;
        }
        
        return list.set(index, element);
    }

    public JSONArray fluentSet(int index, Object element) {
        set(index, element);
        return this;
    }

    public void add(int index, Object element) {
        list.add(index, element);
    }

    public JSONArray fluentAdd(int index, Object element) {
        list.add(index, element);
        return this;
    }

    public Object remove(int index) {
        return list.remove(index);
    }

    public JSONArray fluentRemove(int index) {
        list.remove(index);
        return this;
    }

    public int indexOf(Object o) {
        return list.indexOf(o);
    }

    public int lastIndexOf(Object o) {
        return list.lastIndexOf(o);
    }

    public ListIterator<Object> listIterator() {
        return list.listIterator();
    }

    public ListIterator<Object> listIterator(int index) {
        return list.listIterator(index);
    }

    public List<Object> subList(int fromIndex, int toIndex) {
        return list.subList(fromIndex, toIndex);
    }

    public Object get(int index) {
        return list.get(index);
    }

    public JSONObject getJSONObject(int index) {
        Object value = list.get(index);

        if (value instanceof JSONObject) {
            return (JSONObject) value;
        }

        return (JSONObject) toJSON(value);
    }

    public JSONArray getJSONArray(int index) {
        Object value = list.get(index);

        if (value instanceof JSONArray) {
            return (JSONArray) value;
        }

        return (JSONArray) toJSON(value);
    }

    public <T> T getObject(int index, Class<T> clazz) {
        Object obj = list.get(index);
        return TypeUtils.castToJavaBean(obj, clazz);
    }

    public <T> T getObject(int index, Type type) {
        Object obj = list.get(index);
        if (type instanceof Class) {
            return (T) TypeUtils.castToJavaBean(obj, (Class) type);
        } else {
            String json = JSON.toJSONString(obj);
            return (T) JSON.parseObject(json, type);
        }
    }

    public Boolean getBoolean(int index) {
        Object value = get(index);

        if (value == null) {
            return null;
        }

        return castToBoolean(value);
    }

    public boolean getBooleanValue(int index) {
        Object value = get(index);

        if (value == null) {
            return false;
        }

        return castToBoolean(value).booleanValue();
    }

    public Byte getByte(int index) {
        Object value = get(index);

        return castToByte(value);
    }

    public byte getByteValue(int index) {
        Object value = get(index);

        if (value == null) {
            return 0;
        }

        return castToByte(value).byteValue();
    }

    public Short getShort(int index) {
        Object value = get(index);

        return castToShort(value);
    }

    public short getShortValue(int index) {
        Object value = get(index);

        if (value == null) {
            return 0;
        }

        return castToShort(value).shortValue();
    }

    public Integer getInteger(int index) {
        Object value = get(index);

        return castToInt(value);
    }

    public int getIntValue(int index) {
        Object value = get(index);

        if (value == null) {
            return 0;
        }

        return castToInt(value).intValue();
    }

    public Long getLong(int index) {
        Object value = get(index);

        return castToLong(value);
    }

    public long getLongValue(int index) {
        Object value = get(index);

        if (value == null) {
            return 0L;
        }

        return castToLong(value).longValue();
    }

    public Float getFloat(int index) {
        Object value = get(index);

        return castToFloat(value);
    }

    public float getFloatValue(int index) {
        Object value = get(index);

        if (value == null) {
            return 0F;
        }

        return castToFloat(value).floatValue();
    }

    public Double getDouble(int index) {
        Object value = get(index);

        return castToDouble(value);
    }

    public double getDoubleValue(int index) {
        Object value = get(index);

        if (value == null) {
            return 0D;
        }

        return castToDouble(value);
    }

    public BigDecimal getBigDecimal(int index) {
        Object value = get(index);

        return castToBigDecimal(value);
    }

    public BigInteger getBigInteger(int index) {
        Object value = get(index);

        return castToBigInteger(value);
    }

    public String getString(int index) {
        Object value = get(index);

        return castToString(value);
    }

    public java.util.Date getDate(int index) {
        Object value = get(index);

        return castToDate(value);
    }

    public java.sql.Date getSqlDate(int index) {
        Object value = get(index);

        return castToSqlDate(value);
    }

    public java.sql.Timestamp getTimestamp(int index) {
        Object value = get(index);

        return castToTimestamp(value);
    }

    /**
     * @since  1.2.23
     */
    public <T> List<T> toJavaList(Class<T> clazz) {
        List<T> list = new ArrayList<T>(this.size());

        ParserConfig config = ParserConfig.getGlobalInstance();

        for (Object item : this) {
            T classItem = (T) TypeUtils.cast(item, clazz, config);
            list.add(classItem);
        }

        return list;
    }

    @Override
    public Object clone() {
        return new JSONArray(new ArrayList<Object>(list));
    }

    public boolean equals(Object obj) {
        return this.list.equals(obj);
    }

    public int hashCode() {
        return this.list.hashCode();
    }

    private void readObject(final java.io.ObjectInputStream in) throws IOException, ClassNotFoundException {
        JSONObject.SecureObjectInputStream.ensureFields();
        if (JSONObject.SecureObjectInputStream.fields != null && !JSONObject.SecureObjectInputStream.fields_error) {
            ObjectInputStream secIn = new JSONObject.SecureObjectInputStream(in);
            secIn.defaultReadObject();
            return;
        }

        in.defaultReadObject();
        for (Object item : list) {
            if (item != null) {
                ParserConfig.global.checkAutoType(item.getClass().getName(), null);
            }
        }
    }
}
JSONArray

一些数据转换的API

JSONArray.parseArray("json树字符串")-----------可以返回JSONArray对象

jsonArray对象.toJSONString()------------------------可以转换为字符串便于存入数据库

首先我们需要有一个json树,这里可以自己编写,跟数据库操作的相关方法暂不涉及,这里直接使用相关API搭建,在main方法中

    public static void main(String[] args) {
        JSONArray details=new JSONArray();
        JSONObject tree1=new JSONObject();
        tree1.put("id",1);
        tree1.put("code", "taosir");
        tree1.put("name", "taosir");
        JSONObject tree2=new JSONObject();
        tree2.put("id",2);
        tree2.put("code", "moer");
        tree2.put("name", "moer");
        JSONArray array1=new JSONArray();
        array1.add(tree1);
        array1.add(tree2);
        JSONObject tree3=new JSONObject();
        tree3.put("id",3);
        tree3.put("code", "xixi");
        tree3.put("name", "xixi");
        tree3.put("children", array1);
        JSONObject tree4=new JSONObject();
        tree4.put("id",4);
        tree4.put("code", "jack");
        tree4.put("name", "jack");
        JSONArray array2=new JSONArray();
        array2.add(tree3);
        array2.add(tree4);
        JSONObject tree5=new JSONObject();
        tree5.put("id",5);
        tree5.put("code", "lay");
        tree5.put("name", "lay");
        tree5.put("children", array2);
        JSONObject tree6=new JSONObject();
        tree6.put("id",6);
        tree6.put("code", "haer");
        tree6.put("name", "haer");
        details.add(tree5);
        details.add(tree6);
        System.out.println(details);
    }

[{
    "id":5,
    "code":"lay",
    "name":"lay",
    "children":[{
        "id":3,
        "code":"xixi",
        "name":"xixi",
        "children":[{
            "code":"taosir",
            "name":"taosir",
            "id":1
        },{
            "code":"moer",
            "name":"moer",
            "id":2
        }]
    },{
        "id":4
        "code":"jack",
        "name":"jack"
    }]
},{
    "code":"haer",
    "name":"haer",
    "id":6
}]
生成的json树

点击上面可以查看生成的json树

OK,准备工作完毕,下面进行功能演示。

注意,每演示一个功能点,请注释掉其他的打印语句

首先是查询:

/**
     * 根据单一条件获取节点位置
     * @param body            查询目标的主体内容
     * @param key            筛选匹配条件条件对应--key
     * @param value            筛选匹配条件对应--value
     * @param result        缓存查询结果
     * @return
     */
    public static JSONObject getNode(JSONArray body,String key,Object value,JSONObject result) {
        for (int i = 0; i < body.size(); i++) {
            JSONObject jsonObject =body.getJSONObject(i);
            if (jsonObject.get(key).toString().equals(value.toString())) {
                for (Map.Entry<String, Object> entry : jsonObject.entrySet()) {
                    result.put(entry.getKey(), entry.getValue());
                }
          break; }
else if(jsonObject.getJSONArray("children")!=null) { getNode(jsonObject.getJSONArray("children"), key, value,result); } } return result; }

在main方法调用演示,将前面的打印注释掉

//System.out.println(details);
System.out.println(getNode(details, "id", 4,new JSONObject()));

查询写出来,基本思路对了,其他的操作都类似,简单得多

下面是添加

/**
     * 
     * @param body            需要添加的目标树主体
     * @param key            筛选匹配条件对应的key
     * @param value            筛选匹配条件的值
     * @param index            需要插入的下标位置索引
     * @param node            插入的整体节点
     */
    public static void addNode(JSONArray body,String key,Object value,int index,JSONObject node) {
        for (int i = 0; i < body.size(); i++) {
            if("id".equals(key)&&"0".equals(value.toString())) {
                body.add(index, node);
                break;
            }
            JSONObject jsonObject =body.getJSONObject(i);
            if (jsonObject.get(key).toString().equals(value.toString())) {
                jsonObject.getJSONArray("children").add(index, node);
          break; }
else if(jsonObject.getJSONArray("children")!=null) { addNode(jsonObject.getJSONArray("children"), key, value,index,node); } } }
System.out.println(getNode(details, "id",6 ,new JSONObject()));
JSONObject tree7=new JSONObject();
tree7.put("id",7);
tree7.put("code", "bom");
tree7.put("name", "bom");
addNode(details, "id", 6, 0, tree7);
System.out.println(getNode(details, "id",6 ,new JSONObject()));

可以看到,当节点位置没有子节点时,默认追加,这个时候需要传0,没有考虑越界,可以弄自定义异常处理

System.out.println(getNode(details, "id",6 ,new JSONObject()));
JSONObject tree8=new JSONObject();
tree8.put("id",8);
tree8.put("code", "naonao");
tree8.put("name", "naonao");
addNode(details, "id", 6, 0, tree8);
System.out.println(getNode(details, "id",6 ,new JSONObject()));

这种是已经有节点的情况,可以看到为直接插入索引位置

下面是删除,不保留孩子节点:

    /**
     * 根据单一条件删除节点
     * @param body        需要删除的目标主体
     * @param key        筛选匹配条件对应的key
     * @param value        筛选匹配条件对应的value
     */
    public static void delNode(JSONArray body,String key,Object value) {
        for (int i = 0; i < body.size(); i++) {
            JSONObject jsonObject =body.getJSONObject(i);
            if (jsonObject.get(key).toString().equals(value.toString())) {
                body.remove(i);
                break;
            }else if(jsonObject.getJSONArray("children")!=null) {
                delNode(jsonObject.getJSONArray("children"), key, value);
            }
        }
    }
System.out.println(getNode(details, "id",6 ,new JSONObject()));
delNode(details, "id", 8);
System.out.println(getNode(details, "id",6 ,new JSONObject()));

可以看到刚才加入的节点(id=8)已经被成功删除

下面是修改,可以选择是否保留孩子节点

/**
     * 根据单一条件修改节点
     * @param body        需要修改的目标主体
     * @param key        筛选匹配条件对应的key
     * @param value        筛选匹配条件对应的value
     * @param result    修改节点信息
     * @param isKeep    是否保留孩子节点
     */
    public static void updateNode(JSONArray body,String key,Object value,JSONObject result,boolean isKeep) {
        for (int i = 0; i < body.size(); i++) {
            JSONObject jsonObject =body.getJSONObject(i);
            if (jsonObject.get(key).toString().equals(value.toString())) {
                if(isKeep)
                    result.put("children", jsonObject.getJSONArray("children"));
                body.set(i, result);
                break;
            }else if(jsonObject.getJSONArray("children")!=null) {
                updateNode(jsonObject.getJSONArray("children"), key, value,result,isKeep);
            }
        }
    }

当需要保留孩子节点时:

System.out.println(getNode(details, "id",6 ,new JSONObject()));
JSONObject tree9=new JSONObject();
tree9.put("id",6);
tree9.put("code", "bom");
tree9.put("name", "bom");
updateNode(details, "id", 6, tree9, true);
System.out.println(getNode(details, "id",6 ,new JSONObject()));

当不需要保留孩子节点时:

System.out.println(getNode(details, "id",6 ,new JSONObject()));
JSONObject tree9=new JSONObject();
tree9.put("id",6);
tree9.put("code", "bom");
tree9.put("name", "bom");
updateNode(details, "id", 6, tree9, false);
System.out.println(getNode(details, "id",6 ,new JSONObject()));

以上,为简单的增删查改,根据业务不同会有不同的更改。

虽然业务要求匹配ID即可,不过这里以单一条件的匹配,能正常实现也能应对需要匹配其他字段的情况

每个人的实现方式不同,这里仅是我个人的思路与实现,仅供参考。

新人一枚,如有疑问或建议,欢迎提出!

原文地址:https://www.cnblogs.com/it-taosir/p/9860829.html