Jackson 对象与json数据互转工具类JacksonUtil

news/2024/11/27 23:22:49/

下面是一个基于 Jackson 的工具类 JacksonUtil，用于在 Java 项目中实现对象与 JSON 数据之间的互相转换。该工具类具有简洁、易用、通用的特点。

package com.fy.common.util;import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.module.SimpleModule;
import com.fasterxml.jackson.databind.node.ArrayNode;
import com.fasterxml.jackson.databind.node.ObjectNode;
import com.fasterxml.jackson.databind.type.CollectionType;
import com.fasterxml.jackson.databind.type.MapType;
import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
import com.fasterxml.jackson.datatype.jsr310.deser.LocalDateDeserializer;
import com.fasterxml.jackson.datatype.jsr310.deser.LocalDateTimeDeserializer;
import com.fasterxml.jackson.datatype.jsr310.deser.LocalTimeDeserializer;
import com.fasterxml.jackson.datatype.jsr310.ser.LocalDateSerializer;
import com.fasterxml.jackson.datatype.jsr310.ser.LocalDateTimeSerializer;
import com.fasterxml.jackson.datatype.jsr310.ser.LocalTimeSerializer;
import com.fy.common.constant.ObjectConstant;
import com.fy.common.constant.StringConstant;
import com.fy.common.custom.CustomDateDeserializer;
import com.fy.common.custom.CustomDateSerializer;
import lombok.NonNull;
import org.apache.commons.lang.BooleanUtils;
import org.apache.commons.lang.StringUtils;import java.io.*;
import java.lang.reflect.Type;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.net.URL;
import java.sql.Date;
import java.sql.Time;
import java.sql.Timestamp;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;public enum JacksonUtil {/*** 单例*/i;/*** convert json to javabean or javabean to json.*/private ObjectMapper mapper;private TypeReference<Map<String, Object>> mapType = new TypeReference<Map<String, Object>>() {} ;private TypeReference<List<Map<String, Object>>> listmType = new TypeReference<List<Map<String, Object>>>() {};static {i.mapper = new ObjectMapper();i.mapper.setTimeZone(ObjectConstant.DatexFormatter.TIME_ZONE_E8);// 对于空的对象转json的时候不抛出错误i.mapper.disable(SerializationFeature.FAIL_ON_EMPTY_BEANS);// 禁用遇到未知属性抛出异常i.mapper.disable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES);// 序列化BigDecimal时不使用科学计数法输出i.mapper.configure(JsonGenerator.Feature.WRITE_BIGDECIMAL_AS_PLAIN, true);i.mapper.registerModule(sqltimeModule());i.mapper.registerModule(localtimeModule());}private  static SimpleModule sqltimeModule() {SimpleModule sqltimeModule = new SimpleModule();sqltimeModule.addSerializer(Timestamp.class, new CustomDateSerializer.TimestampSerializer());sqltimeModule.addSerializer(Date.class, new CustomDateSerializer.SqlDateSerializer());sqltimeModule.addSerializer(Time.class, new CustomDateSerializer.SqlTimeSerializer());sqltimeModule.addDeserializer(Timestamp.class, new CustomDateDeserializer.TimestampDeserializer());sqltimeModule.addDeserializer(Date.class, new CustomDateDeserializer.SqlDateDeserializer());sqltimeModule.addDeserializer(Time.class, new CustomDateDeserializer.SqlTimeDeserializer());return sqltimeModule;}private static JavaTimeModule localtimeModule() {JavaTimeModule localtimeModule = new JavaTimeModule();LocalDateTimeSerializer datimeSlizer = new LocalDateTimeSerializer(ObjectConstant.DatexFormatter.STANDARD_DATETIME);LocalDateSerializer dateSlizer = new LocalDateSerializer(ObjectConstant.DatexFormatter.STANDARD_DATE);LocalTimeSerializer timeSlizer = new LocalTimeSerializer(ObjectConstant.DatexFormatter.STANDARD_TIME);LocalDateTimeDeserializer datimeDlizer = new LocalDateTimeDeserializer(ObjectConstant.DatexFormatter.STANDARD_DATETIME);LocalDateDeserializer dateDlizer = new LocalDateDeserializer(ObjectConstant.DatexFormatter.STANDARD_DATE);LocalTimeDeserializer timeDlizer = new LocalTimeDeserializer(ObjectConstant.DatexFormatter.STANDARD_TIME);localtimeModule.addSerializer(LocalDateTime.class, datimeSlizer);localtimeModule.addSerializer(LocalDate.class, dateSlizer);localtimeModule.addSerializer(LocalTime.class, timeSlizer);localtimeModule.addDeserializer(LocalDateTime.class, datimeDlizer);localtimeModule.addDeserializer(LocalDate.class, dateDlizer);localtimeModule.addDeserializer(LocalTime.class, timeDlizer);return localtimeModule;}/*** 	创建一个JSON对象*/public static ObjectNode createObjectNode() {return i.mapper.createObjectNode();}/*** 	创建一个JSON数组*/public static ArrayNode createArrayNode() {return i.mapper.createArrayNode();}/***	 判断一个字符串是否是合法的json格式字符串**/public static boolean isJson(String jsonStr) {try {i.mapper.readTree(jsonStr);return true;} catch (JsonProcessingException e) {return false;}}/*** 	字符串转Json对象**/public static ObjectNode readJsonObject(String jsonStr) {JsonNode node = null;ObjectNode objNode = null;try {node = i.mapper.readTree(jsonStr);if (!node.isArray()) {objNode = (ObjectNode) node;}} catch (IOException e) {throw new RuntimeException(e);}return objNode;}/*** 	字符串转Json数组*/public static ArrayNode readJsonArray(String jsonStr) {JsonNode node = null;ArrayNode arrNode = null;try {node = i.mapper.readTree(jsonStr);if (node.isArray()) {arrNode = (ArrayNode) node;}} catch (IOException e) {throw new RuntimeException(e);}return arrNode;}/*** 	字符串转JsonNode*/public static JsonNode readJson(String jsonStr) {try {return i.mapper.readTree(jsonStr);} catch (IOException e) {throw new RuntimeException(e);}}/*** 	字节数组转JSON*/public static JsonNode readJson(byte[] content) {try {return i.mapper.readTree(content);} catch (IOException e) {throw new RuntimeException(e);}}/*** 将JSON对象转成Map** @param objectNode   json非数组对象* @return Map*/public static Map<String, Object> jsonObjct2Map(ObjectNode objectNode) {return i.mapper.convertValue(objectNode, i.mapType);}/*** 	将JSON对象转成类型** @param objectNode json非数组对象* @return Map*/public static <T> T jsonObjct2Object(ObjectNode objectNode, Class<T> toType) {return i.mapper.convertValue(objectNode, toType);}/*** 	将JSON对象转成List<Map>集合** @param arryNode  json数组对象* @return List*/public static List<Map<String, Object>> jsonArray2List(ArrayNode arryNode) {return i.mapper.convertValue(arryNode, i.listmType);}/*** 	将JsonNode转成指定类型的** @param jsonNode* @return T*/public static <T> T jsonNode2Type(JsonNode jsonNode, TypeReference<T> typeReference) {return i.mapper.convertValue(jsonNode, typeReference);}/*** 	将字符串转成指定class类型对象*/public static <T> T readJson(String jsonStr, Class<T> T) {T obj = null;try {obj = i.mapper.readValue(jsonStr, T);} catch (JsonProcessingException e) {throw new RuntimeException(e);}return obj;}/*** 	将字符串转成指定类型的对象*/public static <T> T readJson(String jsonStr, TypeReference<T> typeReference) {T obj = null;try {obj = i.mapper.readValue(jsonStr, typeReference);} catch (JsonProcessingException e) {throw new RuntimeException(e);}return obj;}/*** URL请求返回结果体转换对象* 案例： URL url = new URL("<a href="https://jsonplaceholder.typicode.com/posts/1">...</a>"); //远程服务URL*       PostDTO post = JacksonUtil.readJson(url, PostDTO.class);*/public static <T> T readJson(@NonNull URL url, Class<T> type) {try {return i.mapper.readValue(url, type);} catch (IOException e) {throw new RuntimeException(e);}}/*** URL请求返回结果体转换对象*/public static <T> T readJson(@NonNull URL url, TypeReference<T> type) {try {return i.mapper.readValue(url, type);} catch (IOException e) {throw new RuntimeException(e);}}/*** URL请求返回结果体转换list集合*/public static <T> List<T> readJsonList(@NonNull URL url, Class<T> type) {try {CollectionType collectionType = i.mapper.getTypeFactory().constructCollectionType(ArrayList.class, type);return i.mapper.readValue(url, collectionType);} catch (IOException e) {throw new RuntimeException(e);}}/*** 输入流转换为对象*/public static <T> T readJson(@NonNull InputStream inputStream, Class<T> type) {try {return i.mapper.readValue(inputStream, type);} catch (IOException e) {throw new RuntimeException(e);}}/*** 输入流转换为对象*/public static <T> T readJson(@NonNull InputStream inputStream, TypeReference<T> type) {try {return i.mapper.readValue(inputStream, type);} catch (IOException e) {throw new RuntimeException(e);}}/*** 读取文件中JSON格式文本转换对象*/public static <T> T readJson(@NonNull File file, Class<T> type) {try {return i.mapper.readValue(file, type);} catch (IOException e) {throw new RuntimeException(e);}}/*** 读取文件中JSON格式文本转换对象*/public static <T> T readJson(@NonNull File file, TypeReference<T> type) {try {return i.mapper.readValue(file, type);} catch (IOException e) {throw new RuntimeException(e);}}/*** 读取文件中JSON格式文本转换（List）对象*/public static <T> List<T> readJsonList(@NonNull File file, Class<T> type) {try {CollectionType collectionType = i.mapper.getTypeFactory().constructCollectionType(ArrayList.class, type);return i.mapper.readValue(file, collectionType);} catch (IOException e) {throw new RuntimeException(e);}}/*** json字符串转换List集合* @param jsonString JSON字符串* @param cls        转换对象* @return list集合* @param <T> 目标对象类型*/public static <T> List<T> readJsonList(@NonNull String jsonString, Class<T> cls) {try {return i.mapper.readValue(jsonString, getCollectionType(cls));} catch (IOException e) {throw new RuntimeException(e);}}/*** Object对象转List集合*/public static <T> List<T> readJsonList(@NonNull Object obj, Class<T> cls) {try {String s = i.mapper.writeValueAsString(obj);return readJsonList(s, cls);} catch (JsonProcessingException e) {throw new RuntimeException(e);}}/*** JSON字符串转换Map集合*/public static Map<String, Object> readJsonMap(@NonNull String json) {if (StringUtils.isEmpty(json)) {return null;}try {MapType mapType = i.mapper.getTypeFactory().constructMapType(HashMap.class, String.class, Object.class);return i.mapper.readValue(json, mapType);} catch (IOException e) {throw new RuntimeException(e);}}/*** 	将java对象转成字符串*/public static String writeJson(Object entity) {String str = StringConstant.Json.EMPTY_OBJECT;if (entity == null) {return str;}try {str = i.mapper.writeValueAsString(entity);} catch (JsonProcessingException e) {throw new RuntimeException(e);}return str;}/*** list集合转换为JSON字符串* @param list list集合* @return JSON字符串* @param <T> 目标对象类型*/public static <T> String writeString(@NonNull List<T> list) {try {return i.mapper.writeValueAsString(list);} catch (JsonProcessingException e) {throw new RuntimeException(e);}}/*** 序列化为JSON*/public static <T> void writeFile(@NonNull String path, List<T> list) {try (Writer writer = new FileWriter(path, true)) {i.mapper.writer().writeValues(writer).writeAll(list);} catch (Exception e) {throw new RuntimeException(e);}}/*** 序列化为JSON*/public static <T> void writeFile(@NonNull String path, T t) {try (Writer writer = new FileWriter(path, true)) {i.mapper.writer().writeValues(writer).write(t);} catch (Exception e) {throw new RuntimeException(e);}}/***	 将对象实体转换成Jackson的ObjectNode*/public static ObjectNode bean2ObjNode(Object bean) {return i.mapper.convertValue(bean, ObjectNode.class);}/*** 将对象转换成JsonNode*/public static JsonNode convertToJsonNode (Object object) {return i.mapper.valueToTree(object);}/*** 将Map转换成JsonNode*/public static JsonNode convertToJsonNode(Map<String,Object> map) {return i.mapper.convertValue(map, JsonNode.class);}/*** 从json串中获取某个字段** @param json JSON字符串* @param key  对象属性名* @return String，默认为 null*/public static String getAsString(String json, String key) {if (StringUtils.isEmpty(json)) {return null;}try {JsonNode jsonNode = getAsJsonObject(json, key);if (null == jsonNode) {return null;}return getAsString(jsonNode);} catch (Exception e) {throw new RuntimeException(e);}}private static String getAsString(JsonNode jsonNode) {return jsonNode.isTextual() ? jsonNode.textValue() : jsonNode.toString();}/*** 从json串中获取某个字段** @param json JSON字符串* @param key  对象属性名* @return int，默认为 0*/public static int getAsInt(String json, String key) {if (StringUtils.isEmpty(json)) {return 0;}try {JsonNode jsonNode = getAsJsonObject(json, key);if (null == jsonNode) {return 0;}return jsonNode.isInt() ? jsonNode.intValue() : Integer.parseInt(getAsString(jsonNode));} catch (Exception e) {throw new RuntimeException(e);}}/*** 从json串中获取某个字段** @param json JSON字符串* @param key  对象属性名* @return long，默认为 0*/public static long getAsLong(String json, String key) {if (StringUtils.isEmpty(json)) {return 0L;}try {JsonNode jsonNode = getAsJsonObject(json, key);if (null == jsonNode) {return 0L;}return jsonNode.isLong() ? jsonNode.longValue() : Long.parseLong(getAsString(jsonNode));} catch (Exception e) {throw new RuntimeException(e);}}/*** 从json串中获取某个字段** @param json JSON字符串* @param key  对象属性名* @return double，默认为 0.0*/public static double getAsDouble(String json, String key) {if (StringUtils.isEmpty(json)) {return 0.0;}try {JsonNode jsonNode = getAsJsonObject(json, key);if (null == jsonNode) {return 0.0;}return jsonNode.isDouble() ? jsonNode.doubleValue() : Double.parseDouble(getAsString(jsonNode));} catch (Exception e) {throw new RuntimeException(e);}}/*** 从json串中获取某个字段** @param json JSON字符串* @param key  对象属性名* @return BigInteger，默认为 0.0*/public static BigInteger getAsBigInteger(String json, String key) {if (StringUtils.isEmpty(json)) {return new BigInteger(String.valueOf(0.00));}try {JsonNode jsonNode = getAsJsonObject(json, key);if (null == jsonNode) {return new BigInteger(String.valueOf(0.00));}return jsonNode.isBigInteger() ? jsonNode.bigIntegerValue() : new BigInteger(getAsString(jsonNode));} catch (Exception e) {throw new RuntimeException(e);}}/*** 从json串中获取某个字段** @param json JSON字符串* @param key  对象属性名* @return BigDecimal，默认为 0.00*/public static BigDecimal getAsBigDecimal(String json, String key) {if (StringUtils.isEmpty(json)) {return new BigDecimal("0.00");}try {JsonNode jsonNode = getAsJsonObject(json, key);if (null == jsonNode) {return new BigDecimal("0.00");}return jsonNode.isBigDecimal() ? jsonNode.decimalValue() : new BigDecimal(getAsString(jsonNode));} catch (Exception e) {throw new RuntimeException(e);}}/*** 从json串中获取某个字段** @param json JSON字符串* @param key  对象属性名* @return boolean, 默认为false*/public static boolean getAsBoolean(String json, String key) {if (StringUtils.isEmpty(json)) {return false;}try {JsonNode jsonNode = getAsJsonObject(json, key);if (null == jsonNode) {return false;}if (jsonNode.isBoolean()) {return jsonNode.booleanValue();} else {if (jsonNode.isTextual()) {String textValue = jsonNode.textValue();if (StringConstant.Number.ONE.equals(textValue)) {return true;} else {return BooleanUtils.toBoolean(textValue);}} else {//numberreturn BooleanUtils.toBoolean(jsonNode.intValue());}}} catch (Exception e) {throw new RuntimeException(e);}}/*** 从json串中获取某个字段** @param json JSON字符串* @param key  对象属性名* @return byte[], 默认为 null*/public static byte[] getAsBytes(String json, String key) {if (StringUtils.isEmpty(json)) {return null;}try {JsonNode jsonNode = getAsJsonObject(json, key);if (null == jsonNode) {return null;}return jsonNode.isBinary() ? jsonNode.binaryValue() : getAsString(jsonNode).getBytes();} catch (Exception e) {throw new RuntimeException(e);}}/*** 从json串中获取某个字段** @param json JSON字符串* @param key  对象属性名* @return object, 默认为 null*/public static <T> T getAsObject(String json, String key, Class<T> type) {if (StringUtils.isEmpty(json)) {return null;}try {JsonNode jsonNode = getAsJsonObject(json, key);if (null == jsonNode) {return null;}JavaType javaType = i.mapper.getTypeFactory().constructType(type);return from(getAsString(jsonNode), javaType);} catch (Exception e) {throw new RuntimeException(e);}}/*** 从json串中获取某个字段** @param json JSON字符串* @param key  对象属性名* @return list, 默认为 null*/public static <T> List<T> getAsList(String json, String key, Class<T> type) {if (StringUtils.isEmpty(json)) {return null;}try {JsonNode jsonNode = getAsJsonObject(json, key);if (null == jsonNode) {return null;}CollectionType collectionType = i.mapper.getTypeFactory().constructCollectionType(ArrayList.class, type);return from(getAsString(jsonNode), collectionType);} catch (Exception e) {throw new RuntimeException(e);}}/*** JSON反序列化*/private static <T> T from(String json, Type type) {if (StringUtils.isEmpty(json)) {return null;}try {JavaType javaType = i.mapper.getTypeFactory().constructType(type);return i.mapper.readValue(json, javaType);} catch (IOException e) {throw new RuntimeException(e);}}/*** 从json串中获取某个字段* @return JsonNode, 默认为 null*/public static JsonNode getAsJsonObject(String json, String key) {try {JsonNode node = i.mapper.readTree(json);if (null == node) {return null;}return node.get(key);} catch (IOException e) {throw new RuntimeException(e);}}/*** 向json中添加属性* @return json*/public static <T> String add(String json, String key, T value) {try {JsonNode node = i.mapper.readTree(json);add(node, key, value);return node.toString();} catch (IOException e) {throw new RuntimeException(e);}}/*** 向json中添加属性*/private static <T> void add(JsonNode jsonNode, String key, T value) {if (value instanceof String) {((ObjectNode) jsonNode).put(key, (String) value);} else if (value instanceof Short) {((ObjectNode) jsonNode).put(key, (Short) value);} else if (value instanceof Integer) {((ObjectNode) jsonNode).put(key, (Integer) value);} else if (value instanceof Long) {((ObjectNode) jsonNode).put(key, (Long) value);} else if (value instanceof Float) {((ObjectNode) jsonNode).put(key, (Float) value);} else if (value instanceof Double) {((ObjectNode) jsonNode).put(key, (Double) value);} else if (value instanceof BigDecimal) {((ObjectNode) jsonNode).put(key, (BigDecimal) value);} else if (value instanceof BigInteger) {((ObjectNode) jsonNode).put(key, (BigInteger) value);} else if (value instanceof Boolean) {((ObjectNode) jsonNode).put(key, (Boolean) value);} else if (value instanceof byte[]) {((ObjectNode) jsonNode).put(key, (byte[]) value);} else {((ObjectNode) jsonNode).put(key, writeJson(value));}}/*** 除去json中的某个属性* @return json*/public static String remove(String json, String key) {try {JsonNode node = i.mapper.readTree(json);((ObjectNode) node).remove(key);return node.toString();} catch (IOException e) {throw new RuntimeException(e);}}/*** 修改json中的属性*/public static <T> String update(String json, String key, T value) {try {JsonNode node = i.mapper.readTree(json);((ObjectNode) node).remove(key);add(node, key, value);return node.toString();} catch (IOException e) {throw new RuntimeException(e);}}/*** 格式化Json(美化)* @return json*/public static String format(String json) {try {JsonNode node = i.mapper.readTree(json);return i.mapper.writerWithDefaultPrettyPrinter().writeValueAsString(node);} catch (IOException e) {throw new RuntimeException(e);}}/*** 获取泛型的Collection Type** @param elementClasses 实体bean* @return JavaType Java类型*/private static JavaType getCollectionType(Class<?>... elementClasses) {return i.mapper.getTypeFactory().constructParametricType(List.class, elementClasses);}}
package com.fy.common.custom;import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonDeserializer;
import lombok.SneakyThrows;import javax.xml.datatype.DatatypeFactory;
import javax.xml.datatype.XMLGregorianCalendar;
import java.io.IOException;
import java.sql.Date;
import java.sql.Time;
import java.sql.Timestamp;
import java.util.GregorianCalendar;/*** 全局日期（针对 java.sql.Date、java.sql.Time、java.sql.TimeStamp三种）* jackson反解析*/
public class CustomDateDeserializer {public static class TimestampDeserializer extends JsonDeserializer<Timestamp> {@Overridepublic Timestamp deserialize(JsonParser p, DeserializationContext ctxt) throws IOException, JsonProcessingException {return Timestamp.valueOf(p.getValueAsString());}}public static class SqlDateDeserializer extends JsonDeserializer<Date> {@Overridepublic Date deserialize(JsonParser p, DeserializationContext ctxt) throws IOException, JsonProcessingException {return Date.valueOf(p.getValueAsString());}}public static class SqlTimeDeserializer extends JsonDeserializer<Time> {@Overridepublic Time deserialize(JsonParser p, DeserializationContext ctxt) throws IOException, JsonProcessingException {return Time.valueOf(p.getValueAsString());}}public static class SqlXMLGregorianCalendarDeserializer extends JsonDeserializer<XMLGregorianCalendar> {@SneakyThrows@Overridepublic XMLGregorianCalendar deserialize(JsonParser p, DeserializationContext ctxt) throws IOException {Date date = Date.valueOf(p.getValueAsString());GregorianCalendar cal = new GregorianCalendar();cal.setTime(date);return DatatypeFactory.newInstance().newXMLGregorianCalendar(cal);}}}
package com.fy.common.custom;import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.SerializerProvider;import javax.xml.datatype.XMLGregorianCalendar;
import java.io.IOException;
import java.sql.Date;
import java.sql.Time;
import java.sql.Timestamp;/*** 全局日期（针对 java.sql.Date、java.sql.Time、java.sql.TimeStamp三种）* jackson解析*/
public class CustomDateSerializer {public static class SqlDateSerializer extends JsonSerializer<Date> {@Overridepublic void serialize(Date value, JsonGenerator gen, SerializerProvider serializers) throws IOException {gen.writeString(value.toString());}}public static class TimestampSerializer extends JsonSerializer<Timestamp> {@Overridepublic void serialize(Timestamp value, JsonGenerator gen, SerializerProvider serializers) throws IOException {gen.writeString(value.toString().substring(0, 19));}}public static class SqlTimeSerializer extends JsonSerializer<Time> {@Overridepublic void serialize(Time value, JsonGenerator gen, SerializerProvider serializers) throws IOException {gen.writeString(value.toString());}}public static class SqlXMLGregorianCalendarSerializer extends JsonSerializer<XMLGregorianCalendar> {@Overridepublic void serialize(XMLGregorianCalendar value, JsonGenerator gen, SerializerProvider serializers) throws IOException {gen.writeNumber(value.toGregorianCalendar().getTimeInMillis());}}}

其中StringConstant.JSON在这篇博客中有分享。
https://blog.csdn.net/qq_41520636/article/details/144006665?spm=1001.2014.3001.5501


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