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[[email protected]]
*/
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[[email protected]]
*/
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());
}
}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);
}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
时间： 2024-11-14 21:37:35