I've seen an Android project structure in the image below. What does "Bean" mean in this structure? or Why does that folder name "Bean"?
Bean in java is basically a single class encapsulate many objects into a single object and there properties can be manipulated by using getter and setter method.We also call it model class. The below code snippet is an example of bean class.
public class Book implements Serializable{
private String isbn;
private String title;
private String author;
private String publisher;
private int pages;
/**
* Default constructor
*/
public Book() {
this.isbn = "";
this.title = "";
this.author = "";
this.publisher = "";
this.pages = 0;
}
public String getIsbn() {
return isbn;
}
public void setIsbn(final String isbn) {
this.isbn = isbn;
}
public String getTitle() {
return title;
}
public void setTitle(final String title) {
this.title = title;
}
public String getAuthor() {
return author;
}
public void setAuthor(final String author) {
this.author = author;
}
public String getPublisher() {
return publisher;
}
public void setPublisher(final String publisher) {
this.publisher = publisher;
}
public int getPages() {
return pages;
}
public void setPages(final int pages) {
this.pages = pages;
}
}
In your case i think the package you pointed contained all the bean classes
I'm developing an Android app which connects to a Springboot server.
The app (using okhttp3 and retrofit) calls the server which returns an array list in an object (Photo Response) below.
The list is populating but the object MediaContentGroup does not populate in any photo object even though the fields of id and title do.
I've debugged through my server to ensure that I am using the correct object names when using #SerializedName.
I'm pretty new to Android development and using springboot, so if anyone could help me to understand why the MediaContentGroup object is always null, I would really appreciate it.
Is there any possible way I've set it to only accept Strings??
Thanks
public class PhotoResponse {
#SerializedName("photoFeed")
#Expose
private PhotoFeed photoFeed;
public PhotoFeed getPhotoFeed() {
return photoFeed;
}
}
public class PhotoFeed {
#SerializedName("photoList")
#Expose
private List<Photo> photoList = new ArrayList<>();
public List<Photo> getPhotoList() {
return photoList;
}
}
public class Photo {
public final static int HD_720_WIDTH = 1280;
public final static int HD_720_HEIGHT = 720;
#SerializedName("id")
#Expose
private String id;
#SerializedName("title")
#Expose
private String title;
#SerializedName("mediaContentGroup")
#Expose
private MediaContentGroup mediaContentGroup;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public void setMediaContentGroup(MediaContentGroup mediaContentGroup){
this.mediaContentGroup = mediaContentGroup;
}
public MediaContentGroup getMediaContentGroup(){
return this.mediaContentGroup;
}
public String getImageUrl() {
return mediaContentGroup.getImages().get(0).getUrl();
}
public String getThumbUrl() {
return mediaContentGroup.getThumbnails().get(0).getUrl();
}
}
public class MediaContentGroup {
#SerializedName("images")
#Expose
public List<MediaContent> images = new ArrayList<>();
public void setImages(List<MediaContent> images){ this.images = images;}
public List<MediaContent> getImages() {
return images;
}
#SerializedName("thumbnails")
#Expose
public List<Thumbnail> thumbnails = new ArrayList<>();
public void setThumbnails(List<Thumbnail> thumbnails){ this.thumbnails = thumbnails;}
public List<Thumbnail> getThumbnails() {
return thumbnails;
}
}
public class Thumbnail {
#SerializedName("url")
#Expose
private String url;
public void setUrl(String url) {
this.url = url;
}
public String getUrl() {
return url;
}
}
I am not so new to Android, but started using retrofit today, I was able to clear all errors, now the response body returns null. I know its something to do with the way my class is set up. I have no idea how to handle an array with arrays. Any help would be appreciated. Thanks
[
My Interface
#GET("/web-api.php?route=feed/web_api/products")
Call<Product> loadProducts(#Query("category") Integer id, #Query("key") String apiKey);
Class
public class Product implements Serializable {
#SerializedName("id")
private long mId;
#SerializedName("name")
private String mname;
#SerializedName("description")
private String mText;
#SerializedName("price")
private Double mprice;
#SerializedName("href")
private String mproductURL;
#SerializedName("thumb")
private String mImageURL;
public Product(long mId, String mname, String mText, Double mprice, String mproductURL, String mImageURL) {
this.mId = mId;
this.mname = mname;
this.mText = mText;
this.mprice = mprice;
this.mproductURL = mproductURL;
this.mImageURL = mImageURL;
}
public long getmId() {
return mId;
}
public void setmId(long mId) {
this.mId = mId;
}
public String getMname() {
return mname;
}
public void setMname(String mname) {
this.mname = mname;
}
public String getmText() {
return mText;
}
public void setmText(String mText) {
this.mText = mText;
}
public Double getMprice() {
return mprice;
}
public void setMprice(Double mprice) {
this.mprice = mprice;
}
public String getMproductURL() {
return mproductURL;
}
public void setMproductURL(String mproductURL) {
this.mproductURL = mproductURL;
}
public String getmImageURL() {
return mImageURL;
}
public void setmImageURL(String mImageURL) {
this.mImageURL = mImageURL;
}
#Override
public String toString() {
return mText;
}
}
Just define a Super class -
public class ResponseDS{
public boolean success;
public Product[] products;
}
And use ResponseDS instead of Product class -
#GET("/web-api.php?route=feed/web_api/products")
Call<ResponseDS> loadProducts(#Query("category") Integer id, #Query("key") String apiKey);
Hope it will help :)
I am using Sugar ORM 1.3.1 and i am trying to save the following objects
public class Article extends SugarRecord<Article> implements Serializable {
#JsonProperty("Categories")
private List<Category> categories = new ArrayList<Category>();
#JsonProperty("Contents")
private List<Content> contents = new ArrayList<Content>();
#JsonProperty("Country")
private CountryRelated country;
#JsonProperty("Description")
private String description;
#JsonProperty("ExpiryDate")
private String expiryDate;
#JsonProperty("ExtraFields")
private List<ExtraField> extraFields = new ArrayList<ExtraField>();
#JsonProperty("Identifier")
private int identifier;
#JsonProperty("ImageURL")
private String imageURL;
#JsonProperty("Name")
private String name;
#JsonProperty("PortalID")
private int portalID;
#JsonProperty("PublishDate")
private String publishDate;
#JsonProperty("Region")
private Region region;
#JsonProperty("Related")
private List<Related> related = new ArrayList<Related>();
#JsonProperty("Newsbite")
private boolean newsbite;
#JsonProperty("ShareURL")
private String shareURL;
#JsonProperty("Tags")
private List<Tag> tags = new ArrayList<Tag>();
#JsonProperty("Type")
private int type;
public Article() {
}
public Article(List<Category> categories, List<Content> contents, List<ExtraField> extraFields, CountryRelated country, String description, String expiryDate, int identifier, String imageURL, String name, boolean newsbite, int portalID, String publishDate, Region region, List<Related> related, String shareURL, List<Tag> tags, int type) {
this.categories = categories;
this.contents = contents;
this.extraFields = extraFields;
this.country = country;
this.description = description;
this.expiryDate = expiryDate;
this.identifier = identifier;
this.imageURL = imageURL;
this.name = name;
this.newsbite = newsbite;
this.portalID = portalID;
this.publishDate = publishDate;
this.region = region;
this.related = related;
this.shareURL = shareURL;
this.tags = tags;
this.type = type;
}
public List<Category> getCategories() {
return categories;
}
public void setCategories(List<Category> categories) {
this.categories = categories;
}
public List<Content> getContents() {
return contents;
}
public void setContents(List<Content> contents) {
this.contents = contents;
}
public List<ExtraField> getExtraFields() {
return extraFields;
}
public void setExtraFields(List<ExtraField> extraFields) {
this.extraFields = extraFields;
}
public CountryRelated getCountry() {
return country;
}
public void setCountry(CountryRelated country) {
this.country = country;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
public String getExpiryDate() {
return expiryDate;
}
public void setExpiryDate(String expiryDate) {
this.expiryDate = expiryDate;
}
public int getIdentifier() {
return identifier;
}
public void setIdentifier(int identifier) {
this.identifier = identifier;
}
public String getImageURL() {
return imageURL;
}
public void setImageURL(String imageURL) {
this.imageURL = imageURL;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public boolean isNewsbite() {
return newsbite;
}
public void setNewsbite(boolean newsbite) {
this.newsbite = newsbite;
}
public int getPortalID() {
return portalID;
}
public void setPortalID(int portalID) {
this.portalID = portalID;
}
public String getPublishDate() {
return publishDate;
}
public void setPublishDate(String publishDate) {
this.publishDate = publishDate;
}
public Region getRegion() {
return region;
}
public void setRegion(Region region) {
this.region = region;
}
public List<Related> getRelated() {
return related;
}
public void setRelated(List<Related> related) {
this.related = related;
}
public String getShareURL() {
return shareURL;
}
public void setShareURL(String shareURL) {
this.shareURL = shareURL;
}
public List<Tag> getTags() {
return tags;
}
public void setTags(List<Tag> tags) {
this.tags = tags;
}
public int getType() {
return type;
}
public void setType(int type) {
this.type = type;
}
}
Category.class
public class Category extends SugarRecord<Category> implements Serializable {
#JsonProperty("Identifier")
private int identifier;
#JsonProperty("Name")
private String name;
public constructor + getters and setters }
Content.class and CountryRelated.class have same structure
after i do article.save() my lists doesnt save . Am i doing something wrong or it doesnt save lists at all ???
I few things to look at.
First. I do not believe that the database will handle a column with the type of List or a type of other Object. When I tried running your code, I received:
Class cannot be read from Sqlite3 database. Please check the type of field categories(java.util.List)
These should be types the database can store. Try serializing your List(s) to Strings to insert them in the db. You can try doing this in your getter and setter. The setter takes the list of objects and converts it to a serialized String, the getter takes the serialized String and converts it back to a list of objects.
In the instance of SugarOrm, you can reference another table and it will create a relationship outlined here:
http://satyan.github.io/sugar/creation.html#why
Notice the "Author" type is just referencing a record from another table in the database.
Second I usually try and set my default values inside my default constructor. so something like:
... property declarations...
public Article() {
this.name = "Default Value";
}
Hope this helps you finish troublshooting!
i just started to android prograamming and found nice tutorial by using imdb api. instead of using xml in this tutorial i would like to use json and for the recevied json i have a problem.
this is the person.json:
[
{
"score":1,
"popularity":3,
"name":"Brad Pitt",
"id":287,
"biography":"test",
"url":"http://www.themoviedb.org/person/287",
"profile":[
{
"image":{
"type":"profile",
"size":"thumb",
"height":68,
"width":45,
"url":"http://d3gtl9l2a4fn1j.cloudfront.net/t/p/w45/w8zJQuN7tzlm6FY9mfGKihxp3Cb.jpg",
"id":"4ea5cb8c2c0588394800006f"
}
},
{
"image":{
"type":"profile",
"size":"profile",
"height":281,
"width":185,
"url":"http://d3gtl9l2a4fn1j.cloudfront.net/t/p/w185/w8zJQuN7tzlm6FY9mfGKihxp3Cb.jpg",
"id":"4ea5cb8c2c0588394800006f"
}
},
{
"image":{
"type":"profile",
"size":"h632",
"height":632,
"width":416,
"url":"http://d3gtl9l2a4fn1j.cloudfront.net/t/p/h632/w8zJQuN7tzlm6FY9mfGKihxp3Cb.jpg",
"id":"4ea5cb8c2c0588394800006f"
}
},
{
"image":{
"type":"profile",
"size":"original",
"height":1969,
"width":1295,
"url":"http://d3gtl9l2a4fn1j.cloudfront.net/t/p/original/w8zJQuN7tzlm6FY9mfGKihxp3Cb.jpg",
"id":"4ea5cb8c2c0588394800006f"
}
}
],
"version":685,
"last_modified_at":"2013-02-16 07:11:15 UTC"
}
]
my two object for them:
public class Person implements Serializable {
private static final long serialVersionUID = 6794898677027141412L;
public String score;
public String popularity;
public String name;
public String id;
public String biography;
public String url;
public String version;
public String lastModifiedAt;
public Profile profile;
}
public class Profile implements Serializable {
private static final long serialVersionUID = -8735669377345509929L;
public ArrayList<Image> imagesList;
}
public class Image implements Serializable {
private static final long serialVersionUID = -2428562977284114465L;
public String type;
public String url;
public String size;
public int width;
public int height;
}
ı couldnt figure out how to retrieve person list by using jackson object mapper.
when i use this one:
ObjectMapper mapper = new ObjectMapper();
Person person= mapper.readValue(jsonResponseString, Person.class);
i got:
02-16 18:34:48.010: W/System.err(376): com.fasterxml.jackson.databind.JsonMappingException: Can not deserialize instance of com.example.imdbsearcher.model.Person out of START_ARRAY token
02-16 18:34:48.180: W/System.err(376): at [Source: java.io.StringReader#40a81778; line: 1, column: 1]
02-16 18:34:48.554: W/System.err(376): at com.fasterxml.jackson.databind.DeserializationContext.mappingException(DeserializationContext.java:599)
02-16 18:34:48.830: W/System.err(376): at com.fasterxml.jackson.databind.DeserializationContext.mappingException(DeserializationContext.java:593)
i have changed the retrieve method with advice of Keith and crdnilfan.
but now i have a problem with the attribute of profile.
i realized that i am missing that one in person object and basicly i have created new profile object and moved imageList to this class.
i have updated POJO's as above.
but now i am getting the same error for the profile.
Can not deserialize instance of com.example.imdbsearcher.model.Profile out of START_ARRAY token
You need to deserialize the list, as your JSON is an array:
List<Person> people = mapper.readValue(
jsonResponseString, new TypeReference<List<Person >>(){});
However, after you do that you will have some additional deserialization errors because of the profile property in your JSON. Checkout: http://jackson.codehaus.org/1.5.7/javadoc/org/codehaus/jackson/annotate/JsonIgnoreProperties.html
Update:
public class Person implements Serializable
{
public List<Object> profile;
public String score;
public String popularity;
public String name;
public String id;
public String biography;
public String url;
public String version;
public String last_modified_at;
}
There are several ways to deal with this. This will give you a linked hash map for Profile.
Alternatively, if you control the JSON format, change the profile syntax to this:
"profile":[
image:...,
image:...
]
That's because you are trying to deserialize a list of Person.class, not one instance. Create another class like this
public class PersonList extends ArrayList<Person> {}
and then use
ArrayList<Person> people = mapper.readValue(jsonResponseString, PersonList.class);
The other two answers clearly explain the reason for the error, it would get rid off the error and it will parse Person object. But for me it failed to parse image objects. With below POJO we can parse the specified json completely, without any issues even in the absence of
#JsonIgnoreProperties
or
mapper.configure(DeserializationConfig.Feature.FAIL_ON_UNKNOWN_PROPERTIES, false);
POJO definition:
public class PersonList extends ArrayList<Person> {}
public class Person implements Serializable {
private static final long serialVersionUID = 6794898677027141412L;
public String score;
public String popularity;
public String name;
public String id;
public String biography;
public String url;
public String version;
#JsonProperty(value="last_modified_at")
public String lastModifiedAt;
public List<Profile> profile;
}
public class Profile implements Serializable {
private static final long serialVersionUID = -8735669377345509929L;
#JsonProperty(value="image")
public Image imagesList;
}
public class Image implements Serializable {
private static final long serialVersionUID = -2428562977284114465L;
public String id;
public String type;
public String url;
public String size;
public int width;
public int height;
}
This should parse the json
String jsonResponseString = readJsonFile("person.json");
ObjectMapper mapper = new ObjectMapper();
PersonList person= mapper.readValue(jsonResponseString, PersonList.class);
or
List<Person> person= mapper.readValue(jsonResponseString,
new TypeReference<List< Person>>(){}); //if we use this we dont have to define PersonList class