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Read JSON Nested element using reflection without using JsonFactory or ObjectMapper

[Unable to access property of another object stored in Arraylist]
I am creating an function to get JSON input in object from RESTful Web service input and format it again in JSON format to call other web service.
I have limitation that I can not use any JSON API for object mapping hence using Java reflection core API.
I am able to create JSON format from Input for simple elements but unable to access nested elements (another user defined POJO class ). I am using arraylist.
Input
{
"GenesisIncidents": {
"service": "Transmission",
"affectedCI": "22BT_ORNC03",
"opt_additionalAffectedItems": [
{
"itemType": "NODE-ID",
"ItemName": "22BT_ORNC03"
},
{
"ItemType": "CCT",
"ItemName": "A_circuit_id"
}]
}
}
GenesisIncidents.class
import java.util.ArrayList;
import java.util.Date;
public class GenesisIncidents {
private String service;
private String affectedCI;
private ArrayList<AdditionalAffectedItems> opt_additionalAffectedItems;
public GenesisIncidents(){}
public String getService() {
return service;
}
public void setService(String service) {
this.service = service;
}
public String getAffectedCI() {
return affectedCI;
}
public void setAffectedCI(String affectedCI) {
this.affectedCI = affectedCI;
}
public ArrayList<AdditionalAffectedItems> getOpt_additionalAffectedItems() {
return opt_additionalAffectedItems;
}
public void setOpt_additionalAffectedItems(ArrayList<AdditionalAffectedItems> opt_additionalAffectedItems) {
this.opt_additionalAffectedItems = opt_additionalAffectedItems;
}
}
AdditionalAffectedItems.class
public class AdditionalAffectedItems {
private String itemType;
private String itemName;
public AdditionalAffectedItems(){
super();
}
public String getItemType() {
return itemType;
}
public void setItemType(String itemType) {
this.itemType = itemType;
}
public String getItemName() {
return itemName;
}
public void setItemName(String itemName) {
this.itemName = itemName;
}
}
Implemetation
public void updateTicketExt(GenesisIncidents genesisIncidents) {
try{
Field allFields[]=genesisIncidents.getClass().getDeclaredFields();
Method allMethods[] = genesisIncidents.getClass().getDeclaredMethods();
String jsonString ="{\r\n \""+genesisIncidents.getClass().getName().toString().substring(48)+"\": {";
final String preStr="\r\n \""; //To create a JSON object format.
final String postStr="\": "; //To create a JSON object format.
int totalNoOfFields=allFields.length;
for (Field field : allFields) {
System.out.println(field.getType());
String getter="get"+StringUtils.capitalize(field.getName());
Method method= genesisIncidents.getClass().getMethod(getter, null);
try{
if(field.getType().toString().contains("Integer"))
jsonString=jsonString + preStr + field.getName() + postStr +method.invoke(genesisIncidents).toString()+",";
else
jsonString=jsonString + preStr + field.getName() + postStr +"\""+method.invoke(genesisIncidents).toString()+"\",";
if(field.getType().toString().contains("ArrayList")){
System.out.println("ArrayListElement found");
genesisIncidents.getOpt_additionalAffectedItems().forEach(obj->{System.out.println(obj.getItemName());});
//convertArrayToJSON(field, genesisIncidents);
}
}catch(NullPointerException npe)
{
System.out.println("Null value in field.");
continue;
}
}
jsonString=jsonString.substring(0,jsonString.length()-1);
jsonString=jsonString+"\r\n }\r\n }";
System.out.println("\n"+jsonString);
}catch(Exception jex){
jex.printStackTrace();
}
}
My below code line is unable to access object stored under array list.
genesisIncidents.getOpt_additionalAffectedItems().forEach(obj->{System.out.println(obj.getItemName());});
OUTPUT
karaf#root>class java.lang.String
class java.lang.String
class java.lang.String
class java.util.ArrayList
ArrayListElement found
null
null
{
"GenesisIncidents": {
"service": "Transmission",
"affectedCI": "22BT_ORNC03",
"opt_additionalAffectedItems": " [org.apache.servicemix.examples.camel.rest.model.AdditionalAffectedItems#5881a 895, org.apache.servicemix.examples.camel.rest.model.AdditionalAffectedItems#399b4e eb]"
}
}

I have fiddled around with your example I have managed to get it working. This will produce the correct JSON string by passing in an instance of a GenesisIncident object. I guess that there is much room for improvement here but this can serve as an example.
public static String genesisToJson(GenesisIncidents incidents) {
try{
StringBuilder jsonBuilder = new StringBuilder();
jsonBuilder.append("{\r\n \"")
.append(incidents.getClass().getSimpleName())
.append("\": {");
Field allFields[] = incidents.getClass().getDeclaredFields();
for (Field field : allFields) {
String getter = getGetterMethod(field);
Method method = incidents.getClass().getMethod(getter, null);
try{
if(field.getType().isAssignableFrom(Integer.class)) {
jsonBuilder.append(preStr).append(field.getName()).append(postStr)
.append(method.invoke(incidents).toString()).append(",");
} else if (field.getType().isAssignableFrom(String.class)) {
jsonBuilder.append(preStr).append(field.getName()).append(postStr).append("\"")
.append(method.invoke(incidents).toString()).append("\",");
} else if (field.getType().isAssignableFrom(List.class)) {
System.out.println("ArrayListElement found");
getInnerObjectToJson(field, incidents.getOptItems(), jsonBuilder);
}
} catch(NullPointerException npe) {
System.out.println("Null value in field.");
continue;
}
}
jsonBuilder.append("\r\n } \r\n }");
return jsonBuilder.toString();
}catch(Exception jex){
jex.printStackTrace();
}
return null;
}
private static void getInnerObjectToJson(Field field, List<AdditionalAffectedItems> items, StringBuilder builder)
throws NoSuchMethodException, InvocationTargetException, IllegalAccessException {
builder.append(preStr).append(field.getName()).append(postStr).append("[");
for (var item : items) {
var fields = List.of(item.getClass().getDeclaredFields());
builder.append("{");
for (var f : fields) {
String getter = getGetterMethod(f);
Method method = item.getClass().getMethod(getter, null);
builder.append(preStr).append(f.getName()).append(postStr).append("\"")
.append(method.invoke(item).toString()).append("\"");
if (!(fields.indexOf(f) == (fields.size() - 1))) {
builder.append(",");
}
}
if (items.indexOf(item) == (items.size() - 1)) {
builder.append("}\r\n");
} else {
builder.append("},\r\n");
}
}
builder.append("]");
}
private static String getGetterMethod(Field field) {
return "get" + StringUtils.capitalize(field.getName());
}

Jackson no suitable constructor found for android.graphics.Bitmap

I'm trying to serialize my Character object with the use of Jackson. The mapper.writeValue method invocation is successful it seems, but when I try to read the value with the use of mapper.readValue I get the following error message:
com.fasterxml.jackson.databind.JsonMappingException: Can not construct instance of android.graphics.Bitmap: no suitable constructor found, can not deserialize from Object value (missing default constructor or creator, or perhaps need to add/enable type information?)
at [Source: java.io.FileReader#9ab6557; line: 1, column: 199] (through reference chain: java.lang.Object[][0]->com.myproj.character.Character["compositeClothes"]->com.myproj.character.clothing.CompositeClothing["clothes"]->java.util.ArrayList[0]->com.myproj.character.clothing.concrete.Hat["bitmap"])
These are my classes:
#JsonTypeInfo(use = JsonTypeInfo.Id.CLASS, include = JsonTypeInfo.As.PROPERTY, property = "#class")
#JsonSubTypes({
#JsonSubTypes.Type(value = Hat.class, name = "hat"),
#JsonSubTypes.Type(value = Necklace.class, name = "necklace"),
#JsonSubTypes.Type(value = Shirt.class, name = "shirt")
})
public interface Clothing {
int getCoolness();
int getrId();
Bitmap getBitmap();
}
My hat class:
public class Hat implements Clothing {
private int rId;
private int coolness;
private Bitmap bitmap;
#JsonCreator
public Hat(#JsonProperty("coolness") int coolness, #JsonProperty("bitmap") Bitmap bitmap) {
rId = R.id.hat_image;
this.coolness = coolness;
this.bitmap = bitmap;
}
public int getrId() {
return rId;
}
#Override
public int getCoolness() {
return coolness;
}
public Bitmap getBitmap() {
return bitmap;
}
}
My composite clothing class:
public class CompositeClothing implements Clothing, Iterable<Clothing> {
#JsonProperty("coolness")
private int coolness = 0;
private List<Clothing> clothes = new ArrayList<>();
public void add(Clothing clothing) {
clothes.add(clothing);
}
public void remove(Clothing clothing) {
clothes.remove(clothing);
}
public Clothing getChild(int index) {
if (index >= 0 && index < clothes.size()) {
return clothes.get(index);
} else {
return null;
}
}
#Override
public Iterator<Clothing> iterator() {
return clothes.iterator();
}
#Override
public int getCoolness() {
return coolness;
}
#Override
public int getrId() {
return 0;
}
#Override
public Bitmap getBitmap() {
return null;
}
}
And my character class:
public class Character implements Observable {
private static final transient Character instance = new Character();
#JsonProperty("compositeClothes")
private CompositeClothing clothes = new CompositeClothing();
#JsonProperty("compositeHeadFeatures")
private CompositeHeadFeature headFeatures = new CompositeHeadFeature();
private transient List<Observer> observers = new ArrayList<>();
#JsonProperty("skin")
private Skin skin;
public void attach(Observer observer) {
observers.add(observer);
}
public void notifyAllObservers() {
for (Observer observer : observers) {
observer.update();
}
}
public void setSkin(Skin skin) {
this.skin = skin;
notifyAllObservers();
}
public Skin.Color getSkinColor() {
return skin.getColor();
}
public Bitmap getSkinBitmap() {
return skin.getBitmap();
}
public boolean hasSkin() {
return skin != null;
}
public void addClothing(Clothing clothing) {
Clothing oldClothing = (Clothing) getSameTypeObjectAlreadyWorn(clothing);
if (oldClothing != null) {
clothes.remove(oldClothing);
}
clothes.add(clothing);
notifyAllObservers();
}
public CompositeClothing getClothes() {
return clothes;
}
private Object getSameTypeObjectAlreadyWorn(Object newClothing) {
Class<?> newClass = newClothing.getClass();
for (Object clothing : clothes) {
if (clothing.getClass().equals(newClass)) {
return clothing;
}
}
return null;
}
public void removeClothing(Clothing clothing) {
clothes.remove(clothing);
}
public void addHeadFeature(HeadFeature headFeature) {
HeadFeature oldHeadFeature = (HeadFeature) getSameTypeObjectAlreadyWorn(headFeature);
if (oldHeadFeature != null) {
headFeatures.remove(oldHeadFeature);
}
headFeatures.add(headFeature);
notifyAllObservers();
}
public void removeHeadFeature(HeadFeature headFeature) {
headFeatures.remove(headFeature);
}
public CompositeHeadFeature getHeadFeatures() {
return headFeatures;
}
public static Character getInstance() {
return instance;
}
}
The code that I'm using to persist and then read the data:
File charactersFile = new File(getFilesDir() + File.separator + "characters.ser");
ObjectMapper mapper = new ObjectMapper()
.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.NONE)
.setVisibility(PropertyAccessor.FIELD, JsonAutoDetect.Visibility.ANY);
try (FileWriter fileOut = new FileWriter(charactersFile, false)) {
List<Character> characters = Arrays.asList(character);
mapper.writeValue(fileOut, characters);
} catch (IOException e) {
e.printStackTrace();
}
Character[] characters = null;
try (FileReader fileIn = new FileReader(charactersFile)) {
characters = mapper.readValue(fileIn, Character[].class);
} catch (IOException e) {
e.printStackTrace();
}
Thanks!

If your bitmaps come from assets or resources, there is no point on saving the bitmaps to JSON. That would be a waste of CPU time and disk space. Instead, store a value in the JSON that will allow you to identify the asset or resource to display. However, bear in mind that resource IDs (e.g., R.drawable.foo) can vary between app releases, so that is not a good durable identifier for the image.

I have similar requirement in my app where I need to store drawable data in JSON. I solved it by storing only its string name. For example, if I have resource R.drawable.testBmp then I store it in JSON like :
{
...
"mydrawable" : "testBmp"
}
Then at run time, I will read it and convert is as drawable like following code:
JSONObject jsonObj;
...
String bmpName = jsonObj.getString("mydrawable");
int resId = context.getResources().getIdentifier(bmpName,
"drawable",
context.getPackageName());
Drawable bmp = ContextCompat.getDrawable(context,resId);

C# dll method call from Java

Has anyone an idea about what is wrong with my attempt to call a method from a C# dll in my Java code?
Here is my example:
Java code:
public class CsDllHandler {
public interface IKeywordRun extends Library {
public String KeywordRun(String action, String xpath, String inputData,
String verifyData);
}
private static IKeywordRun jnaInstance = null;
public void runDllMethod(String action, String xpath, String inputData,
String verifyData) {
NativeLibrary.addSearchPath(${projectDllName},
"${projectPath}/bin/x64/Debug");
jnaInstance = (IKeywordRun) Native.loadLibrary(
${projectDllName}, IKeywordRun.class);
String csResult = jnaInstance.KeywordRun(action, xpath, inputData,
verifyData);
System.out.println(csResult);
}
}
And in C#:
[RGiesecke.DllExport.DllExport]
public static string KeywordRun(string action, string xpath, string inputData, string verifyData) {
return "C# here";
}
The Unmanaged Exports nuget should be enough for me to call this method (in theory) but I have some strange error:
Exception in thread "main" java.lang.Error: Invalid memory access
at com.sun.jna.Native.invokePointer(Native Method)
at com.sun.jna.Function.invokePointer(Function.java:470)
at com.sun.jna.Function.invokeString(Function.java:651)
at com.sun.jna.Function.invoke(Function.java:395)
at com.sun.jna.Function.invoke(Function.java:315)
at com.sun.jna.Library$Handler.invoke(Library.java:212)
at com.sun.proxy.$Proxy0.KeywordRun(Unknown Source)
at auto.test.keywords.utils.CsDllHandler.runDllMethod(CsDllHandler.java:34)
at auto.test.keywords.runner.MainClass.main(MainClass.java:24)

Well, after another day of research and "trial and error" I have found the cause of my problem and a solution.
The cause was that my C# dll had a dependency on log4net.dll. For running a static method from a standalone C# dll the code from the question is all you need.
The solution for using C# dll with dependencies is to create another dll with no dependency and to load the original dll in this adapter with reflection. In Java you should load the adapter dll with jna and call any exported method. I was able not only to execute methods from the adapter but also to configure log4net with reflection and Java
Here is my code:
(C#)
public class CSharpDllHandler {
private static Logger log = Logger.getLogger(CSharpDllHandler.class);
public interface IFrameworkAdapter extends Library {
public String runKeyword(String action, String xpath, String inputData,
String verifyData);
public String configureLog4net(String log4netConfigPath);
public String loadAssemblies(String frameworkDllPath,
String log4netDllPath);
}
private static IFrameworkAdapter jnaAdapterInstance = null;
private String jnaSearchPath = null;
public CSharpDllHandler(String searchPath) {
this.jnaSearchPath = searchPath;
// add to JNA search path
System.setProperty("jna.library.path", jnaSearchPath);
// load attempt
jnaAdapterInstance = (IFrameworkAdapter) Native.loadLibrary(
"FrameworkAdapter", IFrameworkAdapter.class);
}
public String loadAssemblies(String frameworkDllPath, String log4netDllPath) {
String csResult = jnaAdapterInstance.loadAssemblies(frameworkDllPath,
log4netDllPath);
log.debug(csResult);
return csResult;
}
public String runKeyword(String action, String xpath, String inputData,
String verifyData) {
String csResult = jnaAdapterInstance.runKeyword(action, xpath,
inputData, verifyData);
log.debug(csResult);
return csResult;
}
public String configureLogging(String log4netConfigPath) {
String csResult = jnaAdapterInstance
.configureLog4net(log4netConfigPath);
log.debug(csResult);
return csResult;
}
public String getJnaSearchPath() {
return jnaSearchPath;
}
}
In the main method just use something like this:
CSharpDllHandler dllHandler = new CSharpDllHandler(
${yourFrameworkAdapterDllLocation});
dllHandler.loadAssemblies(
${yourOriginalDllPath},${pathToTheUsedLog4netDllFile});
dllHandler.configureLogging(${log4net.config file path});
dllHandler.runKeyword("JAVA Action", "JAVA Xpath", "JAVA INPUT",
"JAVA VERIFY");
dllHandler.runKeyword("JAVA Action2", "JAVA Xpath2", "JAVA INPUT2",
"JAVA VERIFY2");
In C# I have the desired methods on the original dll:
public static string KeywordRun(string action, string xpath, string inputData, string verifyData) {
log.Debug("Action = " + action);
log.Debug("Xpath = " + xpath);
log.Debug("InputData = " + inputData);
log.Debug("VerifyData = " + verifyData);
return "C# UserActions result: "+ action+" "+xpath+" "+inputData+" "+verifyData;
}
and all the magic is in the DLL Adapter:
namespace FrameworkAdapter {
[ComVisible(true)]
public class FwAdapter {
private const String OK="OK";
private const String frameworkEntryClassName = "${nameOfTheDllClass with method to run }";
private const String log4netConfiguratorClassName = "log4net.Config.XmlConfigurator";
private static Assembly frameworkDll = null;
private static Type frameworkEntryClass = null;
private static MethodInfo keywordRunMethod = null;
private static Assembly logDll = null;
private static Type logEntryClass = null;
private static MethodInfo logConfigureMethod = null;
private static String errorMessage = "OK";
[RGiesecke.DllExport.DllExport]
public static string loadAssemblies(string frameworkDllPath, string log4netDllPath) {
try {
errorMessage = LoadFrameworkDll(frameworkDllPath, frameworkEntryClassName);
LoadFrameworkMethods("KeywordRun", "Setup", "TearDown");
errorMessage = LoadLogAssembly(log4netDllPath, log4netConfiguratorClassName);
if (errorMessage.CompareTo(OK) == 0)
errorMessage = LoadLogMethods("Configure");
}
catch (Exception e) {
return e.Message;
}
return errorMessage;
}
[RGiesecke.DllExport.DllExport]
public static string configureLog4net(string log4netConfigPath) {
if (errorMessage.CompareTo("OK") == 0) {
StringBuilder sb = new StringBuilder();
sb.AppendLine("Try to configure Log4Net");
try {
FileInfo logConfig = new FileInfo(log4netConfigPath);
logConfigureMethod.Invoke(null, new object[] { logConfig });
sb.AppendLine("Log4Net configured");
}
catch (Exception e) {
sb.AppendLine(e.InnerException.Message);
}
return sb.ToString();
}
return errorMessage;
}
[RGiesecke.DllExport.DllExport]
public static string runKeyword(string action, string xpath, string inputData, string verifyData) {
StringBuilder sb = new StringBuilder();
object result = null;
try {
result = keywordRunMethod.Invoke(null, new object[] { action, xpath, inputData, verifyData });
sb.AppendLine(result.ToString());
}
catch (Exception e) {
sb.AppendLine(e.InnerException.Message);
}
return sb.ToString();
}
private static String LoadFrameworkDll(String dllFolderPath, String entryClassName) {
try {
frameworkDll = Assembly.LoadFrom(dllFolderPath);
Type[] dllTypes = frameworkDll.GetExportedTypes();
foreach (Type t in dllTypes)
if (t.FullName.Equals(entryClassName)) {
frameworkEntryClass = t;
break;
}
}
catch (Exception e) {
return e.InnerException.Message;
}
return OK;
}
private static String LoadLogAssembly(String dllFolderPath, String entryClassName) {
try {
logDll = Assembly.LoadFrom(dllFolderPath);
Type[] dllTypes = logDll.GetExportedTypes();
foreach (Type t in dllTypes)
if (t.FullName.Equals(entryClassName)) {
logEntryClass = t;
break;
}
}
catch (Exception e) {
return e.InnerException.Message;
}
return OK;
}
private static String LoadLogMethods(String logMethodName) {
try {
logConfigureMethod = logEntryClass.GetMethod(logMethodName, new Type[] { typeof(FileInfo) });
}
catch (Exception e) {
return e.Message;
}
return OK;
}
private static void LoadFrameworkMethods(String keywordRunName, String scenarioSetupName, String scenarioTearDownName) {
///TODO load the rest of the desired methods here
keywordRunMethod = frameworkEntryClass.GetMethod(keywordRunName);
}
}
}
Running this code will provide all the logged messages from the original C# DLL to the Java console output (and to a file if configured). In a similar way, we can load any other needed dll files for runtime.
Please forgive my [very probable wrong] way of doing things in C# with reflection, I'm new to this language.

Java Reflection/BeanUtils issue

I'm trying to populate a bean with some table driven attribute:value pairs. I retrieve them from a MySQL table, and populate a hashmap just fine. I iterate through the hashmap, and if I use PropertyUtils.setProperty() I get a "Class does not have setter for *" error. If I use BeanUtils.setProperty() the bean never gets populated. Here's the sample:
public class DBDrivenPayloadHandler extends GDE{
DbDrivenPayloadHandlerBean bean;
#SuppressWarnings("rawtypes")
public void populateBean() throws Exception {
ITransaction trans = new MySQLTransaction();
IAdapterDataMapDAO adapterDataMap = new MySQLAdapterDataMapDAO();
adapterDataMap.setTransaction(trans);
HashMap<String, String> values = adapterDataMap.getHashMap(super.getCurrentAccountId());
//hashmap gets populated correctly with correct variable names and values != "-1";
DbDrivenPayloadHandlerBean bean = new DbDrivenPayloadHandlerBean();
//We have a bean with all the intialized variable values
Iterator it = values.entrySet().iterator();
while (it.hasNext()) {
Map.Entry entry = (Map.Entry)it.next();
try {
PropertyUtils.setProperty(bean, (String) entry.getKey(), entry.getValue());
//PropertyUtils will give a setter not found error. BeanUtils never sets the values.
} catch (Exception e) {
e.printStackTrace();
}
}
}
public void getInfo(String fileName) {
try {
populateBean();
} catch (Exception e) {
e.printStackTrace();
}
APPTS_FULLNAME_POS = bean.getAPPTS_FULLNAME_POS();
APPTS_DATETIME_POS = bean.getAPPTS_DATETIME_POS();
//Both still -1;
super.getInfo(filename);
}
And here's the Bean (or at least some of it):
public class DbDrivenPayloadHandlerBean {
int APPTS_FULLNAME_POS = -1;
int APPTS_DATETIME_POS = -1;
public DbDrivenPayloadHandlerBean() {
super();
}
public int getAPPTS_FULLNAME_POS() {
return APPTS_FULLNAME_POS;
}
public void setAPPTS_FULLNAME_POS(String APPTS_FULLNAME_POS) {
this.APPTS_FULLNAME_POS = Integer.parseInt(APPTS_FULLNAME_POS);
}
public int getAPPTS_DATETIME_POS() {
return APPTS_DATETIME_POS;
}
public void setAPPTS_DATETIME_POS(String APPTS_DATETIME_POS) {
this.APPTS_DATETIME_POS = Integer.parseInt(APPTS_DATETIME_POS);
}
Sorry guys, BeanUtils does the trick. I just don't want to be allowing setters that take Strings. I guess reflection does the casting for you. Apologies.

Solution as stated above: don't try to cast for BeanUtils.
public class DBDrivenPayloadHandler extends GDE{
DbDrivenPayloadHandlerBean bean;
#SuppressWarnings("rawtypes")
public void populateBean() throws Exception {
ITransaction trans = new MySQLTransaction();
IAdapterDataMapDAO adapterDataMap = new MySQLAdapterDataMapDAO();
adapterDataMap.setTransaction(trans);
HashMap<String, String> values = adapterDataMap.getHashMap(super.getCurrentAccountId());
this.bean = new DbDrivenPayloadHandlerBean();
Iterator it = values.entrySet().iterator();
while (it.hasNext()) {
Map.Entry entry = (Map.Entry)it.next();
try {
BeanUtils.setProperty(bean, (String) entry.getKey(), entry.getValue());
} catch (Exception e) {
e.printStackTrace();
}
}
}
public void getInfo(String fileName) {
try {
populateBean();
} catch (Exception e) {
e.printStackTrace();
}
APPTS_FULLNAME_POS = bean.getAPPTS_FULLNAME_POS();
APPTS_DATETIME_POS = bean.getAPPTS_DATETIME_POS();
//Both still -1;
super.getInfo(filename);
}
Bean
public class DbDrivenPayloadHandlerBean {
int APPTS_FULLNAME_POS = -1;
int APPTS_DATETIME_POS = -1;
public DbDrivenPayloadHandlerBean() {
super();
}
public int getAPPTS_FULLNAME_POS() {
return APPTS_FULLNAME_POS;
}
public void setAPPTS_FULLNAME_POS(int APPTS_FULLNAME_POS) {
this.APPTS_FULLNAME_POS = APPTS_FULLNAME_POS;
}
public int getAPPTS_DATETIME_POS() {
return APPTS_DATETIME_POS;
}
public void setAPPTS_DATETIME_POS(String APPTS_DATETIME_POS) {
this.APPTS_DATETIME_POS = APPTS_DATETIME_POS;
}

Java warning and error (read object)

My goal: save one ArrayList to a .dat file, after read this file and in the end print this array.
To save the ArrayList, "equipas" is one ArrayList< Equipa>, I use this function:
saveMyFile("Equipas.dat", (Object) equipas);
To read:
public static ArrayList<Equipa> readMyFile(String s){
ArrayList<Equipa> novo = new ArrayList<Equipa>();
try {
ObjectInputStream ois = new ObjectInputStream(new FileInputStream(s));
novo = (ArrayList<Equipa>) ois.readObject();
ois.close();
}
catch(IOException er) { System.out.println(er.getMessage()); }
catch(ClassNotFoundException er) { System.out.println(er.getMessage()); }
return novo;}
In this read function, I have one Compilation Warning: "…uses unchecked or unsafe operations. Recompile with - Xlint:unchecked for details."
To save:
public static void saveMyFile(String s, Object o)
{
try {
ObjectOutputStream oos = new ObjectOutputStream( new FileOutputStream(s));
oos.writeObject(o);
oos.flush();
oos.close();
}
catch(IOException e) { System.out.println(e.getMessage()); }
}
Finally, I want to print the ArrayList's info:
ArrayList<Equipa> cena = new ArrayList<Equipa>();
cena=(ArrayList<Equipa>) readMyFile("Equipas.dat");
for(Equipa e:cena)
e.toString();
Error when I try to run:
" writing aborted; java.io.NotSerializableException: Equipa"
Equipa havs the Serializable:
import java.util.*;
import java.io.*;
public class Equipa implements Serializable
{
private String nome;
private Carro carro;
private ArrayList<Piloto> pilotos;
private double tempoDecorrido;
private int pontos;
private boolean desistiu;
private int voltaDesistencia;
private Piloto piloto;
/**
* Constructor for objects of class Equipa
*/
public Equipa()
{
this.nome = "NA";
this.carro = null;
this.pilotos = new ArrayList<Piloto>();
this.tempoDecorrido = 0;
this.pontos = 0;
this.desistiu = false;
this.voltaDesistencia = 0;
this.piloto = null;
}
public Equipa(String nome, Carro carro, ArrayList<Piloto> pilotos)
{
this.nome = nome;
this.carro = carro;
//this.pilotos = new ArrayList<Piloto>(pilotos);
this.pilotos = pilotos;
this.tempoDecorrido = 0;
this.pontos = 0;
this.desistiu = false;
this.voltaDesistencia = 0;
//this.piloto = pilotos.get(0);
}
public Equipa (Equipa e)
{
this.nome = e.getNome();
this.carro = e.getCarro();
this.pilotos = e.getPilotos();
this.tempoDecorrido = e.getTempoDecorrido();
this.pontos = e.getPontos();
this.desistiu = e.getDesistiu();
this.voltaDesistencia = e.getVoltaDesistencia();
//this.piloto = e.getPiloto();
}
/** Getters */
public String getNome()
{
return this.nome;
}
public Carro getCarro()
{
return this.carro;
}
public ArrayList<Piloto> getPilotos()
{
return new ArrayList<Piloto>(this.pilotos);
}
public double getTempoDecorrido()
{
return this.tempoDecorrido;
}
public int getPontos()
{
return this.pontos;
}
public boolean getDesistiu()
{
return this.desistiu;
}
public int getVoltaDesistencia()
{
return this.voltaDesistencia;
}
public Piloto getPiloto()
{
return this.piloto;
}
/** Setters */
public void setNome(String nome)
{
this.nome = nome;
}
public void setCarro(Carro carro)
{
this.carro = carro;
}
public void setPilotos(ArrayList<Piloto> pilotos)
{
this.pilotos = new ArrayList<Piloto>(pilotos);
}
public void setTempoDecorrido(double tempoDecorrido)
{
this.tempoDecorrido = tempoDecorrido;
}
public void setPontos(int pontos)
{
this.pontos = pontos;
}
public void setDesistiu(boolean desistiu)
{
this.desistiu = desistiu;
}
public void setVoltaDesistencia(int voltaDesistencia)
{
this.voltaDesistencia = voltaDesistencia;
}
public void setPiloto(Piloto piloto)
{
this.piloto = piloto;
}
/** Outros Métodos */
public Equipa clone()
{
return new Equipa(this);
}
public boolean equals(Equipa e)
{
if(this.nome == e.getNome())
return true;
else
return false;
}
public String getStringPilotos()
{
String s = new String();
for(Piloto p: this.pilotos)
s = (s + ", " + p.getNome());
return s;
}
public String toString()
{
return new String("Nome da equipa: " + nome + "; Categoria do carro: " + carro.getClass().getName() + "; Marca e modelo: " + carro.getMarca() + " " + carro.getModelo() + "; Pilotos: " + getStringPilotos())+"\n";
}

Implementing Serializable means that serialization is permitted, but not necessarily that it is possible. For it to work, everything referenced by Equipa must also be either primitive or Serializable (and so on, recursively). Is this the case?

Warning in the read function is the result of generics in java. You won't be able to suppress it, unless you use #SuppressWarnings("unchecked") to ignore it.
If you are sure you are reading an ArrayList<Equipa>, you can ignore it without any problem.
With the Equipa code, I can try to point to the Serializable problem: make sure that Carro and Piloto classes are also Serializables. You can add the code of theses classes if you are not sure.

The only type-safer way would be do a custom serialization, using writeObject(OutputStream) and readObjectInputStream say on a class ArrayListOfEquipa maybe using Equipa[] (ArrayList.toArray()).
Not really attractive, if the warning would be the only reason.