无法从START_ARRAY标记中反序列化java.lang.String的实例

我是Jackson解析器的新手。 我的代码运行正常，直到今天。 我无法弄清楚错误。

Exception in thread "main" com.fasterxml.jackson.databind.JsonMappingException: Can not deserialize instance of java.lang.String out of START_ARRAY token at [Source: line: 1, column: 1095] (through reference chain: JsonGen["platforms"]) at com.fasterxml.jackson.databind.JsonMappingException.from(JsonMappingException.java:163) at com.fasterxml.jackson.databind.DeserializationContext.mappingException(DeserializationContext.java:588) at com.fasterxml.jackson.databind.deser.std.JdkDeserializers$StringDeserializer.deserialize(JdkDeserializers.java:90) at com.fasterxml.jackson.databind.deser.std.JdkDeserializers$StringDeserializer.deserialize(JdkDeserializers.java:59) at com.fasterxml.jackson.databind.deser.SettableBeanProperty.deserialize(SettableBeanProperty.java:336) at com.fasterxml.jackson.databind.deser.impl.MethodProperty.deserializeAndSet(MethodProperty.java:89) at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:290) at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:112) at com.fasterxml.jackson.databind.deser.std.CollectionDeserializer.deserialize(CollectionDeserializer.java:226) at com.fasterxml.jackson.databind.deser.std.CollectionDeserializer.deserialize(CollectionDeserializer.java:203) at com.fasterxml.jackson.databind.deser.std.CollectionDeserializer.deserialize(CollectionDeserializer.java:23) at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:2563) at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:1789) at BossMan.candie(BossMan.java:49) at Hilda.main(Hilda.java:81) 

以下是URL调用和对象映射器的代码：

 public class BossMan { public String[] candie () throws JsonParseException, JsonMappingException, IOException { URL jsonUrl = new URL("http://www.dishanywhere.com/radish/v20/dol/home/carousels/shows.json"); ObjectMapper objmapper = new ObjectMapper(); List jsongen = objmapper.readValue(jsonUrl, new TypeReference<List>() {}); String[] shows = new String [jsongen.size()]; int i = 0; for(JsonGen element : jsongen) { shows[i++]=element.getName(); } return shows; } } 

这是POJO类：

 import java.util.List; public class JsonGen{ private String _type; private List cast; private List clips; private Common_sense_data common_sense_data; private String common_sense_id; private List crew; private String description; private List episodes; private Number franchise_id; private List genres; private String guid; private Images images; private boolean is_locked; private boolean is_mobile; private boolean is_parental_locked; private String kind; private String mobile_networks; private String most_recent_full_episode_added_date; private String name; private List networks; private String platforms; private List ratings; private String release_date; private List season_filters; private String slug; private String tms_id; public String get_type(){ return this._type; } public void set_type(String _type){ this._type = _type; } public List getCast(){ return this.cast; } public void setCast(List cast){ this.cast = cast; } public List getClips(){ return this.clips; } public void setClips(List clips){ this.clips = clips; } public Common_sense_data getCommon_sense_data(){ return this.common_sense_data; } public void setCommon_sense_data(Common_sense_data common_sense_data){ this.common_sense_data = common_sense_data; } public String getCommon_sense_id(){ return this.common_sense_id; } public void setCommon_sense_id(String common_sense_id){ this.common_sense_id = common_sense_id; } public List getCrew(){ return this.crew; } public void setCrew(List crew){ this.crew = crew; } public String getDescription(){ return this.description; } public void setDescription(String description){ this.description = description; } public List getEpisodes(){ return this.episodes; } public void setEpisodes(List episodes){ this.episodes = episodes; } public Number getFranchise_id(){ return this.franchise_id; } public void setFranchise_id(Number franchise_id){ this.franchise_id = franchise_id; } public List getGenres(){ return this.genres; } public void setGenres(List genres){ this.genres = genres; } public String getGuid(){ return this.guid; } public void setGuid(String guid){ this.guid = guid; } public Images getImages(){ return this.images; } public void setImages(Images images){ this.images = images; } public boolean getIs_locked(){ return this.is_locked; } public void setIs_locked(boolean is_locked){ this.is_locked = is_locked; } public boolean getIs_mobile(){ return this.is_mobile; } public void setIs_mobile(boolean is_mobile){ this.is_mobile = is_mobile; } public boolean getIs_parental_locked(){ return this.is_parental_locked; } public void setIs_parental_locked(boolean is_parental_locked){ this.is_parental_locked = is_parental_locked; } public String getKind(){ return this.kind; } public void setKind(String kind){ this.kind = kind; } public String getMobile_networks(){ return this.mobile_networks; } public void setMobile_networks(String mobile_networks){ this.mobile_networks = mobile_networks; } public String getMost_recent_full_episode_added_date(){ return this.most_recent_full_episode_added_date; } public void setMost_recent_full_episode_added_date(String most_recent_full_episode_added_date){ this.most_recent_full_episode_added_date = most_recent_full_episode_added_date; } public String getName(){ return this.name; } public void setName(String name){ this.name = name; } public List getNetworks(){ return this.networks; } public void setNetworks(List networks){ this.networks = networks; } public String getPlatforms(){ return this.platforms; } public void setPlatforms(String platforms){ this.platforms = platforms; } public List getRatings(){ return this.ratings; } public void setRatings(List ratings){ this.ratings = ratings; } public String getRelease_date(){ return this.release_date; } public void setRelease_date(String release_date){ this.release_date = release_date; } public List getSeason_filters(){ return this.season_filters; } public void setSeason_filters(List season_filters){ this.season_filters = season_filters; } public String getSlug(){ return this.slug; } public void setSlug(String slug){ this.slug = slug; } public String getTms_id(){ return this.tms_id; } public void setTms_id(String tms_id){ this.tms_id = tms_id; } } 

这是主要function：

 public class Hilda { public static boolean b ; public static WebDriver driver; public static int countingCrows(WebDriver driver) throws InterruptedException{ int i,j=0,k=0; for(i=1; i<=2; i++){ for(j=1; j<=6; j++){ if(!(i==1&&j==6)){ b = driver.findElement(By.xpath("//div[2]/div[5]/div[3]/div/div/div/div[1]/div/div[2]/div[2]/div/div["+i+"]/ul/li["+j+"]/div/a/img")).isEnabled(); k++; //System.out.println("k inner loop:"+k); } if(i==1&&j==5){ Thread.sleep(5000); try{ boolean c = driver.findElement(By.xpath("//div[2]/div[5]/div[3]/div/div/div/div[1]/div/div[2]/div[2]/div/div[1]/ul/li[6]/div/a/img")).isEnabled(); if(c){ k++; //System.err.println("k inside j==5 for sixsth element:"+k); } }catch (Exception e) { System.err.println("sixsth elemnet not found in first row"); } } } if(i==1&&j==5){ Thread.sleep(5000); driver.findElement(By.xpath("//*[@class='carousel-control left']")).click(); } } System.out.println("total no :"+k); return k; } public static String[] unchained(WebDriver driver) throws InterruptedException{ Thread.sleep(5000); int j = countingCrows(driver); int i,k=0; String[] singleText1 = new String[11]; if(j==11){ for(i=1; i<=2; i++){ for(j=1; j<=6; j++){ if(!(i==1&&j==6)){ singleText1[k] = driver.findElement(By.xpath("//div[2]/div[5]/div[3]/div/div/div/div[1]/div/div[2]/div[2]/div/div["+i+"]/ul/li["+j+"]/div/a/img")).getAttribute("id"); //boolean b = driver.findElement(By.xpath("//div[2]/div[5]/div[3]/div/div/div/div[1]/div/div[2]/div[2]/div/div["+i+"]/ul/li["+j+"]/div/a/img")).isEnabled(); //System.out.print(j-1+"-"+singleText1[k]); System.out.println("-"+b); k++; }else { System.err.println("element div[1] div[6] is not present"); } } if(j==5){ Thread.sleep(5000); driver.findElement(By.xpath("//*[@class='carousel-control left']")).click(); } } } return singleText1; } public static void main(String[] args) throws InterruptedException, JsonParseException, JsonMappingException, IOException { WebDriver driver = new SafariDriver(); driver.get("http://www.dishanywhere.com"); Thread.sleep(5000); String [] cottonSack =unchained(driver); System.out.println("*******************************************************"); int j = countingCrows(driver); /*for(int i= 0;i<=j-1;i++){ System.out.println(cottonSack[i]); }*/ BossMan calvin = new BossMan(); String[] dogs = calvin.candie(); for(int k=0;k<cottonSack.length;k++){ boolean c = dogs[k].equalsIgnoreCase(cottonSack[k]); if(c){ System.out.println("Comparing json data- " +dogs[k]+" with webpage data- "+cottonSack[k]+" and Result is- "+c); }else { System.out.println("Comparing json data- " +dogs[k]+" with webpage data- "+cottonSack[k]+" Result- "+c); } } } } 

Answer 1

错误是：

无法在[Source：line：1，column：1095]的START_ARRAY标记中反序列化java.lang.String的实例（通过引用链：JsonGen [“ platforms ”]）

在JSON中， platforms看起来像这样：

 "platforms": [ { "platform": "iphone" }, { "platform": "ipad" }, { "platform": "android_phone" }, { "platform": "android_tablet" } ] 

所以尝试将你的pojo改成这样的东西：

 private List platforms; public List getPlatforms(){ return this.platforms; } public void setPlatforms(List platforms){ this.platforms = platforms; } 

编辑 ：您也需要更改mobile_networks 。 看起来像这样：

 private List mobile_networks; public List getMobile_networks() { return mobile_networks; } public void setMobile_networks(List mobile_networks) { this.mobile_networks = mobile_networks; }