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Having a few issues when trying to store values in a HashMap

I'm trying to create a program where the user can create a new person which will be stored in a HashMap. Further you can also lend DVD's across from these persons that I want to be stored. The problem arrives when I'm trying to use the method NyPerson, when the program just refuses to store the new name in the HashMap.
Here's my code(Lot's of code so bear with me):
the class with the nyPerson method:
import java.util.*;
class DVDAdministrasjon {
private HashMap<String, Person> navneliste = new HashMap<String, Person>();
public void nyPerson(String navnPerson) {
if(navneliste.containsKey(navnPerson)) {
System.out.println(navnPerson + " er allerde i listen");
} else {
Person nyPerson = new Person(navnPerson);
navneliste.put(navnPerson, nyPerson);
}
}
public void kjop(String navnPerson, String navnDVD) {
if (navneliste.containsKey(navnPerson)) {
navneliste.get(navnPerson).kjop(navnDVD);
} else {
System.out.println("Det er ingen personer som heter " + navnPerson);
}
}
public void laan (String navnLaaner, String navnUtlaaner, String navnDVD) {
if (navnLaaner.equals(navnUtlaaner)) {
System.out.println("Du kan ikke laane en DVD fra deg selv");
} else if (navneliste.containsKey(navnLaaner) &&
navneliste.containsKey(navnUtlaaner)) {
Person utlaaner = navneliste.get(navnUtlaaner);
Person laaner = navneliste.get(navnLaaner);
if (utlaaner.ledig(navnDVD)) {
laaner.laan(navnDVD, utlaaner);
} else {
System.out.println("Den DVD-en er utlaant eller eies ikke av denne personen");
}
} else {
System.out.println("Sjekk at laaner og utlaaner eksisterer");
}
}
public void retur (String navnPerson, String navnDVD) {
if (navneliste.containsKey(navnPerson)) {
navneliste.get(navnPerson).retur(navnDVD);
} else {
System.out.println("Det er ingen personer som heter " + navnPerson);
}
}
public void visPerson(String navnPerson) {
if (navnPerson.equals("*")) {
for (Person person : navneliste.values()) {
person.printDVDer();
}
} else if (navneliste.containsKey(navnPerson)){
navneliste.get(navnPerson).printDVDer();
} else {
System.out.println("Det er ingen personer som heter " + navnPerson);
}
}
public void visOversikt() {
for (Person person : navneliste.values()) {
person.oversikt();
}
}
public void printPersoner(){
for(Person person : navneliste.values())
System.out.println(person);
}
public void printArkiv(String navnPerson) {
navneliste.get(navnPerson).printArkiv();
}
public void avslutt(){
System.out.println("Goodbye");
System.exit(0);
}
}
my Person class:
import java.util.*;
class Person {
private String navn;
private HashMap<String, DVD> arkiv = new HashMap<String, DVD>();
private HashMap<String, DVD> laante = new HashMap<String, DVD>();
private HashMap<String, DVD> utlaante = new HashMap<String, DVD>();
public Person(String navn) {
this.navn = navn;
}
public void kjop(String navn) {
if (arkiv.containsKey(navn)) {
System.out.println("Du eier allerede denne dvd'en");
} else {
DVD nyDVD = new DVD(navn, this);
arkiv.put(navn, nyDVD);
}
}
public void laan(String navnDVD, Person utlaaner) {
laante.put(navnDVD, utlaaner.utlaan(navnDVD));
}
public DVD utlaan(String navnDVD) {
DVD utlaanDVD = arkiv.get(navnDVD);
utlaante.put(navnDVD, utlaanDVD);
return utlaanDVD;
}
public void retur(String navnDVD) {
if (laante.containsKey(navnDVD)) {
laante.remove(navnDVD).retur();
} else {
System.out.println(navn + " laaner ikke denne dvd-en");
}
}
public void faaTilbake(String tilbake) {
utlaante.remove(tilbake);
}
public boolean ledig(String navnDVD) {
return (arkiv.containsKey(navnDVD) && !utlaante.containsKey(navnDVD));
}
public void printArkiv() {
for (DVD dvd : arkiv.values()) {
System.out.println(dvd);
}
}
public void printDVDer() {
System.out.println("\n" + navn + ":");
System.out.println("Eier:");
for (String key : arkiv.keySet()) {
System.out.println("+ " + key);
}
System.out.println("Laaner:");
for (String key : laante.keySet()) {
System.out.println("- " + key);
}
}
public void oversikt() {
System.out.println("\n" + navn + ":");
System.out.println("Eier: " + arkiv.size());
System.out.println("Laant: " + laante.size());
System.out.println("Utlaant: " + utlaante.size());
}
public String toString() {
return this.navn;
}
}
DVD class:
import java.util.*;
class DVD {
private Person eier;
private Person laaner;
private String navn;
public DVD(String navn, Person eier) {
this.navn = navn;
this.eier = eier;
this.laaner = null;
}
public Person getEier() {
return this.eier;
}
public String toString() {
return this.navn;
}
public void retur() {
eier.faaTilbake(navn);
}
}
And here's my main(so far):
import java.util.*;
public class DVDMain{
public static void main(String [] args){
Scanner tastatur = new Scanner(System.in);
String alternativ = "";
while(!alternativ.equals("7")){
System.out.println("MENY FOR DVD-ADMINISTRASJON");
System.out.println("1. Ny person");
System.out.println("2. Kjop");
System.out.println("3. Laan");
System.out.println("4. Vis");
System.out.println("5. Oversikt");
System.out.println("6. Retur");
System.out.println("7. Avslutt");
alternativ = tastatur.nextLine();
DVDAdministrasjon dvdadmin = new DVDAdministrasjon();
if (alternativ.equals("1")){
System.out.println("Hva heter den nye personen?");
String nyperson = tastatur.nextLine();
dvdadmin.nyPerson(nyperson);
System.out.println(nyperson + " er registrert!");
}
else if (alternativ.equals("2")){
System.out.println("Hvem har kjopt DVD-en?");
String navnPerson = tastatur.nextLine();
System.out.println("Hva er tittelen paa DVD-en?");
String navnDVD = tastatur.nextLine();
dvdadmin.kjop(navnPerson, navnDVD);
}
else if(alternativ.equals("3")){
System.out.println("Hvem vil laane DVD-en?");
String navnLaaner = tastatur.nextLine();
System.out.println("Hvem skal DVD-en laanes fra?");
String navnUtlaaner = tastatur.nextLine();
System.out.println("Hva er tittelen paa DVD-en?");
String navnDVD = tastatur.nextLine();
dvdadmin.laan(navnLaaner, navnUtlaaner, navnDVD);
}
}
}
}

As far as I understand, you start your application and type in 1 to add a new person. If you do it again, the person is not found in the map. The problem is, that you instantiate a new DVDAdministrasjon in every run of the loop, so everytime a person or new name is added, the map along with the whole object dvdadmin is overwritten.
To fix this, simply create your dvdadmin instance outside of the loop. As a further remark, always close I/O resources to avoid resource leaks, in your case the Scanner.

Getting the output from a arraylist

Im fairly new to java and ive been doing som searching for an answer to my problem but i just cant seem to get the output from the arraylist.
I get a red mark under Ordtildikt String arrayoutput = kontrollObjekt.Ordtildikt;saying it cannot be resolved or is not a field. The program is supposed to get userinput and create an arraylist from the input
Interface class
import javax.swing.JOptionPane;
public class Grensesnitt {
public static void main(String[] args) {
Grensesnitt Grensesnitt = new Grensesnitt();
Grensesnitt.meny();
}
Kontroll kontrollObjekt = new Kontroll();
private final String[] ALTERNATIVER = {"Registrere ord","Skriv dikt","Avslutt"};
private final int REG = 0;
private final int SKRIV = 1;
public void meny() {
boolean fortsett = true;
while(fortsett) {
int valg = JOptionPane.showOptionDialog(
null,
"Gjør et valg:",
"Prosjektmeny",
JOptionPane.DEFAULT_OPTION,
JOptionPane.PLAIN_MESSAGE,
null,
ALTERNATIVER,
ALTERNATIVER[0]);
switch(valg) {
case REG: regNy();
break;
case SKRIV: regDikt();
break;
default: fortsett = false;
}
}
}
int i = 0;
public void regNy() {
while(i<=16)
{
String Ord = JOptionPane.showInputDialog("Skriv or til diktet: ");
kontrollObjekt.regNy(Ord);
//String Diktord = JOptionPane.showInputDialog("Skriv ord til diktet: ");
//kontrollObjekt.regNy(Diktord);
i = i + 1;
}
}
public void regDikt() {
String arrayoutput = kontrollObjekt.Ordtildikt;
JOptionPane.showMessageDialog(null, arrayoutput);
}
//JOptionPane.showMessageDialog(null, kontrollObjekt.Diktord);
}
Controll Class
import java.util.ArrayList;
public class Kontroll {
public ArrayList<String> Diktord = new ArrayList<String>();
public void regNy(String Ord) {
Diktord.add(Ord);
Diktord.add("\n");
}
public String Ordtildikt(String Ord) {
return Ord=Diktord.toString();
}
}

This is a method, not a variable.
kontrollObjekt.Ordtildikt;
You are trying to call this?
public String Ordtildikt(String Ord) {
return Ord=Diktord.toString();
}
1) Make it return Diktord.toString();
2) Get rid of String Ord unless you are going to use that parameter
3) Actually call the method, e.g. Put some parenthesis.
String arrayoutput = kontrollObjekt.Ordtildikt();
Also, I think this should be the correct regNy method unless you want to falsely report that the list is twice its size.
public void regNy(String Ord) {
Diktord.add(Ord + "\n");
}

Spring mvc, making a menu data object

I'm really a newbie to JAVA, spring mvc.
And my understanding for "code" is so poor that I can't even think of how I'm going to get through with upcoming errors.
So this question will sound like " Do this for me!". ( It will do, actually )
Anyway, I'm trying to make a two-depth menu. Its structure looks like this below.
TopMenu
::: menuNo
::: menuName
::: memberType
::: url
::: sort
::: subMenus
::: menuNo
::: menuName
::: memberType
::: url
::: sort
TopMenu2
::: menuNo2
::: menuName2
::: memberType2
::: url2
.
.
.
.
So I made a bean class for this.
public class MenuInfoBean {
private String menuNo;
private String menuName;
private String memberType;
private String url;
private int sort;
List<MenuInfoBean> subMenus;
public MenuInfoBean() {
}
public String getMenuNo() {
return menuNo;
}
public void setMenuNo(String menuNo) {
this.menuNo = menuNo;
}
public String getMenuName() {
return menuName;
}
public void setMenuName(String menuName) {
this.menuName = menuName;
}
public String getMemberType() {
return memberType;
}
public void setMemberType(String memberType) {
this.memberType = memberType;
}
public String getUrl() {
return url;
}
public void setUrl(String url) {
this.url = url;
}
public int getSort() {
return sort;
}
public void setSort(int sort) {
this.sort = sort;
}
public List<MenuInfoBean> getSubMenus() {
return subMenus;
}
public void setSubMenus(MenuInfoBean subMenus) {
subMenus.menuName = subMenus.menuName;
subMenus.memberType = subMenus.memberType;
subMenus.url = subMenus.url;
subMenus.sort = subMenus.sort;
}
}
Which database will be used is not decided yet, so I'm temporarily using properties for menu data.
#TopMenu List
topmenu = M1000,M9000
#SubMenu List
M1000.submenu =
M9000.submenu = M9001,M9002,M9003,M9004
#TopMenu Info
#M1000 APPLICATION
M1000.menuName=APPLICATION
M1000.url=
M1000.memberType=00,10
M1000.sort=1
#M9000 ADMIN
M9000.menuName=ADMIN
M9000.url=/SYS01/memberList.mon
M9000.memberType=00,10
M9000.sort=1
#SubMenu Info
#M9000 ADMIN's
M9001.menuName=Member mgmt
M9001.url=/SYS01/memberList.mon
M9001.memberType=00,10
M9001.sort=1
M9002.menuName=menu2
M9002.url=/SYS01/memberList.mon
M9002.memberType=00,10
M9002.sort=1
M9003.menuName=menu3
M9003.url=/SYS01/memberList.mon
M9003.memberType=00,10
M9003.sort=1
M9004.menuName=menu4
M9004.url=/SYS01/memberList.mon
M9004.memberType=00,10
M9004.sort=1
And here I fetch the data and try to put them into a List.
public class MenuManager {
public List<MenuInfoBean> getMenus(String permissionCode) {
LabelProperties msgResource = LabelProperties.getInstance();
MenuInfoBean menuInfo = new MenuInfoBean();
List<MenuInfoBean> menuList = new ArrayList<MenuInfoBean>();
String topMenu = msgResource.getProperty("topmenu");
String[] topMenuItems = topMenu.split(",");
for (int i = 0; topMenuItems.length > i; i++ ) {
String subMenuName = msgResource.getProperty(topMenuItems[i] + ".submenu");
if ( subMenuName.isEmpty() == false ) {
menuInfo.setMenuName(msgResource.getProperty(subMenuName + ".menuName"));
menuInfo.setMemberType(msgResource.getProperty(subMenuName + ".memberType"));
menuInfo.setUrl(msgResource.getProperty(subMenuName + ".url"));
menuInfo.setSort(Integer.parseInt(msgResource.getProperty(subMenuName + ".sort")));
menuInfo.setSubMenus(menuInfo);
} else {
menuInfo.setMenuName("");
menuInfo.setSubMenus(menuInfo);
}
menuInfo.setMenuNo("");
menuInfo.setMenuName(msgResource.getProperty(topMenuItems[i] + ".menuName"));
menuInfo.setMemberType(msgResource.getProperty(topMenuItems[i] + ".memberType"));
menuInfo.setUrl(msgResource.getProperty(topMenuItems[i] + ".url"));
menuInfo.setSort(Integer.parseInt(msgResource.getProperty(topMenuItems[i] + ".sort")));
menuList.add(menuInfo);
}
return menuList;
}
}
getProperty method works great. It gets the properties value correctly.
But as you may noticed, there's some null data is being made.
to ignore this NullPointerException, I made
List<MenuInfoBean> menuList = new ArrayList<MenuInfoBean>();
So the exception has been successfully avoided. But another error comes up which isn't important in this post....
Anyway, while trying to solve the new error, I looked into the menuInfo data and found out something wrong was going on.
The subMenus was holding the topMenu's data!
Here's the question, How can I make this menu with MenuInfoBean like the structure I mentioned on the top of this post?
And why subMenus data was holding topMenu's properties?
I set subMenus data first, and topMenu data later! why this happens?

First of all I am updating the domain object by adding a additional method add(Meun)
import java.util.ArrayList;
import java.util.List;
public class MenuInfoBean
{
private String menuNo;
private String menuName;
private String memberType;
private String url;
private int sort;
List<MenuInfoBean> subMenus;
public MenuInfoBean()
{
}
public String getMenuNo()
{
return menuNo;
}
public void setMenuNo(String menuNo)
{
this.menuNo = menuNo;
}
public String getMenuName()
{
return menuName;
}
public void setMenuName(String menuName)
{
this.menuName = menuName;
}
public String getMemberType()
{
return memberType;
}
public void setMemberType(String memberType)
{
this.memberType = memberType;
}
public String getUrl()
{
return url;
}
public void setUrl(String url)
{
this.url = url;
}
public int getSort()
{
return sort;
}
public void setSort(int sort)
{
this.sort = sort;
}
public List<MenuInfoBean> getSubMenus()
{
return subMenus;
}
// This is new method added to the bean
public void addSubMenuItem(MenuInfoBean menuInfoBean)
{
if (subMenus == null)
subMenus = new ArrayList<MenuInfoBean>();
subMenus.add(menuInfoBean);
}
}
Here is the class that generate the menu and return (look at the get menu method):
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import org.apache.commons.lang.StringUtils;
public class MenuExtractionComponent
{
public List<MenuInfoBean> getMenus(String permissionCode)
{
LabelProperties msgResource = LabelProperties.getInstance();
List<MenuInfoBean> menuList = new ArrayList<MenuInfoBean>();
String topMenu = msgResource.getProperty("topmenu");
List<String> topMenuItems = new ArrayList<String>();
// Checking is top menu empty
if (StringUtils.isNotBlank(topMenu))
{
topMenuItems.addAll(Arrays.asList(topMenu.split(",")));
}
for (String topMenuItem : topMenuItems)
{
// Setting top menu details
MenuInfoBean menuInfo = new MenuInfoBean();
menuInfo.setMenuNo("");
menuInfo.setMenuName(msgResource.getProperty(topMenuItem + ".menuName"));
menuInfo.setMemberType(msgResource.getProperty(topMenuItem + ".memberType"));
menuInfo.setUrl(msgResource.getProperty(topMenuItem + ".url"));
menuInfo.setSort(Integer.parseInt(msgResource.getProperty(topMenuItem + ".sort")));
String subMenu = msgResource.getProperty(topMenuItem + ".submenu");
List<String> subMenuItems = new ArrayList<String>();
// Checking is sub menu empty
if (StringUtils.isNotBlank(subMenu))
{
subMenuItems.addAll(Arrays.asList(subMenu.split(",")));
}
for (String subMenuItem : subMenuItems)
{
MenuInfoBean subMenuInfo = new MenuInfoBean();
subMenuInfo.setMenuName(msgResource.getProperty(subMenuItem + ".menuName"));
subMenuInfo.setMemberType(msgResource.getProperty(subMenuItem + ".memberType"));
subMenuInfo.setUrl(msgResource.getProperty(subMenuItem + ".url"));
subMenuInfo.setSort(Integer.parseInt(msgResource.getProperty(subMenuItem + ".sort")));
menuInfo.addSubMenuItem(subMenuInfo);
}
menuList.add(menuInfo);
}
return menuList;
}
}

Printing all variables value from a class

I have a class with information about a Person that looks something like this:
public class Contact {
private String name;
private String location;
private String address;
private String email;
private String phone;
private String fax;
public String toString() {
// Something here
}
// Getters and setters.
}
I want toString() to return this.name +" - "+ this.locations + ... for all variables. I was trying to implement it using reflection as shown from this question but I can't manage to print instance variables.
What is the correct way to solve this?

From Implementing toString:
public String toString() {
StringBuilder result = new StringBuilder();
String newLine = System.getProperty("line.separator");
result.append( this.getClass().getName() );
result.append( " Object {" );
result.append(newLine);
//determine fields declared in this class only (no fields of superclass)
Field[] fields = this.getClass().getDeclaredFields();
//print field names paired with their values
for ( Field field : fields ) {
result.append(" ");
try {
result.append( field.getName() );
result.append(": ");
//requires access to private field:
result.append( field.get(this) );
} catch ( IllegalAccessException ex ) {
System.out.println(ex);
}
result.append(newLine);
}
result.append("}");
return result.toString();
}

Why do you want to reinvent the wheel when there are opensource that are already doing the job pretty nicely.
Both apache common-langs and spring support some very flexible builder pattern
For apache, here is how you do it reflectively
#Override
public String toString()
{
return ToStringBuilder.reflectionToString(this);
}
Here is how you do it if you only want to print fields that you care about.
#Override
public String toString()
{
return new ToStringBuilder(this)
.append("name", name)
.append("location", location)
.append("address", address)
.toString();
}
You can go as far as "styling" your print output with non-default ToStringStyle or even customizing it with your own style.
I didn't personally try spring ToStringCreator api, but it looks very similar.

If you are using Eclipse, this should be easy:
1.Press Alt+Shift+S
2.Choose "Generate toString()..."
Enjoy! You can have any template of toString()s.
This also works with getter/setters.

Generic toString() one-liner, using reflection and style customization:
import org.apache.commons.lang3.builder.ReflectionToStringBuilder;
import org.apache.commons.lang3.builder.ToStringStyle;
...
public String toString()
{
return ReflectionToStringBuilder.toString(this, ToStringStyle.SHORT_PREFIX_STYLE);
}

When accessing the field value, pass the instance rather than null.
Why not use code generation here? Eclipse, for example, will generate a reasoble toString implementation for you.

Another simple approach is to let Lombok generate the toString method for you.
For this:
Simply add Lombok to your project
Add the annotation #ToString to the definition of your class
Compile your class/project, and it is done
So for example in your case, your class would look like this:
#ToString
public class Contact {
private String name;
private String location;
private String address;
private String email;
private String phone;
private String fax;
// Getters and setters.
}
Example of output in this case:
Contact(name=John, location=USA, address=SF, email=foo#bar.com, phone=99999, fax=88888)
More details about how to use the annotation #ToString.
NB: You can also let Lombok generate the getters and setters for you, here is the full feature list.

If the output from ReflectionToStringBuilder.toString() is not enough readable for you, here is code that:
1) sorts field names alphabetically
2) flags non-null fields with asterisks in the beginning of the line
public static Collection<Field> getAllFields(Class<?> type) {
TreeSet<Field> fields = new TreeSet<Field>(
new Comparator<Field>() {
#Override
public int compare(Field o1, Field o2) {
int res = o1.getName().compareTo(o2.getName());
if (0 != res) {
return res;
}
res = o1.getDeclaringClass().getSimpleName().compareTo(o2.getDeclaringClass().getSimpleName());
if (0 != res) {
return res;
}
res = o1.getDeclaringClass().getName().compareTo(o2.getDeclaringClass().getName());
return res;
}
});
for (Class<?> c = type; c != null; c = c.getSuperclass()) {
fields.addAll(Arrays.asList(c.getDeclaredFields()));
}
return fields;
}
public static void printAllFields(Object obj) {
for (Field field : getAllFields(obj.getClass())) {
field.setAccessible(true);
String name = field.getName();
Object value = null;
try {
value = field.get(obj);
} catch (IllegalArgumentException | IllegalAccessException e) {
e.printStackTrace();
}
System.out.printf("%s %s.%s = %s;\n", value==null?" ":"*", field.getDeclaringClass().getSimpleName(), name, value);
}
}
test harness:
public static void main(String[] args) {
A a = new A();
a.x = 1;
B b = new B();
b.x=10;
b.y=20;
System.out.println("=======");
printAllFields(a);
System.out.println("=======");
printAllFields(b);
System.out.println("=======");
}
class A {
int x;
String z = "z";
Integer b;
}
class B extends A {
int y;
private double z = 12345.6;
public int a = 55;
}

Addition with #cletus answer, You have to fetch all model fields(upper hierarchy) and set field.setAccessible(true) to access private members. Here is the full snippet:
#Override
public String toString() {
StringBuilder result = new StringBuilder();
String newLine = System.getProperty("line.separator");
result.append(getClass().getSimpleName());
result.append( " {" );
result.append(newLine);
List<Field> fields = getAllModelFields(getClass());
for (Field field : fields) {
result.append(" ");
try {
result.append(field.getName());
result.append(": ");
field.setAccessible(true);
result.append(field.get(this));
} catch ( IllegalAccessException ex ) {
// System.err.println(ex);
}
result.append(newLine);
}
result.append("}");
result.append(newLine);
return result.toString();
}
private List<Field> getAllModelFields(Class aClass) {
List<Field> fields = new ArrayList<>();
do {
Collections.addAll(fields, aClass.getDeclaredFields());
aClass = aClass.getSuperclass();
} while (aClass != null);
return fields;
}

i will get my answer as follow:
import java.io.IOException;
import java.io.Writer;
import java.lang.reflect.Array;
import java.lang.reflect.Field;
import java.util.HashMap;
import java.util.Map;
public class findclass {
public static void main(String[] args) throws Exception, IllegalAccessException {
new findclass().findclass(new Object(), "objectName");
new findclass().findclass(1213, "int");
new findclass().findclass("ssdfs", "String");
}
public Map<String, String>map=new HashMap<String, String>();
public void findclass(Object c,String name) throws IllegalArgumentException, IllegalAccessException {
if(map.containsKey(c.getClass().getName() + "#" + Integer.toHexString(c.hashCode()))){
System.out.println(c.getClass().getSimpleName()+" "+name+" = "+map.get(c.getClass().getName() + "#" + Integer.toHexString(c.hashCode()))+" = "+c);
return;}
map.put(c.getClass().getName() + "#" + Integer.toHexString(c.hashCode()), name);
Class te=c.getClass();
if(te.equals(Integer.class)||te.equals(Double.class)||te.equals(Float.class)||te.equals(Boolean.class)||te.equals(Byte.class)||te.equals(Long.class)||te.equals(String.class)||te.equals(Character.class)){
System.out.println(c.getClass().getSimpleName()+" "+name+" = "+c);
return;
}
if(te.isArray()){
if(te==int[].class||te==char[].class||te==double[].class||te==float[].class||te==byte[].class||te==long[].class||te==boolean[].class){
boolean dotflag=true;
for (int i = 0; i < Array.getLength(c); i++) {
System.out.println(Array.get(c, i).getClass().getSimpleName()+" "+name+"["+i+"] = "+Array.get(c, i));
}
return;
}
Object[]arr=(Object[])c;
for (Object object : arr) {
if(object==null)
System.out.println(c.getClass().getSimpleName()+" "+name+" = null");
else {
findclass(object, name+"."+object.getClass().getSimpleName());
}
}
}
Field[] fields=c.getClass().getDeclaredFields();
for (Field field : fields) {
field.setAccessible(true);
if(field.get(c)==null){
System.out.println(field.getType().getSimpleName()+" "+name+"."+field.getName()+" = null");
continue;
}
findclass(field.get(c),name+"."+field.getName());
}
if(te.getSuperclass()==Number.class||te.getSuperclass()==Object.class||te.getSuperclass()==null)
return;
Field[]faFields=c.getClass().getSuperclass().getDeclaredFields();
for (Field field : faFields) {
field.setAccessible(true);
if(field.get(c)==null){
System.out.println(field.getType().getSimpleName()+" "+name+"<"+c.getClass().getSuperclass().getSimpleName()+"."+field.getName()+" = null");
continue;
}
Object check=field.get(c);
findclass(field.get(c),name+"<"+c.getClass().getSuperclass().getSimpleName()+"."+field.getName());
}
}
public void findclass(Object c,String name,Writer writer) throws IllegalArgumentException, IllegalAccessException, IOException {
if(map.containsKey(c.getClass().getName() + "#" + Integer.toHexString(c.hashCode()))){
writer.append(c.getClass().getSimpleName()+" "+name+" = "+map.get(c.getClass().getName() + "#" + Integer.toHexString(c.hashCode()))+" = "+c+"\n");
return;}
map.put(c.getClass().getName() + "#" + Integer.toHexString(c.hashCode()), name);
Class te=c.getClass();
if(te.equals(Integer.class)||te.equals(Double.class)||te.equals(Float.class)||te.equals(Boolean.class)||te.equals(Byte.class)||te.equals(Long.class)||te.equals(String.class)||te.equals(Character.class)){
writer.append(c.getClass().getSimpleName()+" "+name+" = "+c+"\n");
return;
}
if(te.isArray()){
if(te==int[].class||te==char[].class||te==double[].class||te==float[].class||te==byte[].class||te==long[].class||te==boolean[].class){
boolean dotflag=true;
for (int i = 0; i < Array.getLength(c); i++) {
writer.append(Array.get(c, i).getClass().getSimpleName()+" "+name+"["+i+"] = "+Array.get(c, i)+"\n");
}
return;
}
Object[]arr=(Object[])c;
for (Object object : arr) {
if(object==null){
writer.append(c.getClass().getSimpleName()+" "+name+" = null"+"\n");
}else {
findclass(object, name+"."+object.getClass().getSimpleName(),writer);
}
}
}
Field[] fields=c.getClass().getDeclaredFields();
for (Field field : fields) {
field.setAccessible(true);
if(field.get(c)==null){
writer.append(field.getType().getSimpleName()+" "+name+"."+field.getName()+" = null"+"\n");
continue;
}
findclass(field.get(c),name+"."+field.getName(),writer);
}
if(te.getSuperclass()==Number.class||te.getSuperclass()==Object.class||te.getSuperclass()==null)
return;
Field[]faFields=c.getClass().getSuperclass().getDeclaredFields();
for (Field field : faFields) {
field.setAccessible(true);
if(field.get(c)==null){
writer.append(field.getType().getSimpleName()+" "+name+"<"+c.getClass().getSuperclass().getSimpleName()+"."+field.getName()+" = null"+"\n");
continue;
}
Object check=field.get(c);
findclass(field.get(c),name+"<"+c.getClass().getSuperclass().getSimpleName()+"."+field.getName(),writer);
}
}
}

Adding user input to ArrayList using do-while loop

I am trying to add user input to an Arraylist using a do-while loop however I keep ending up with a list consisting of only the final item inputed repeated several times.
public static ArrayList<Item> purchaseItems()
{
ArrayList<Item> toBuy = new ArrayList<Item>();
String response;
System.out.println("What would you like to purchase? (type \"done\" to end) ");
do {
response = in.nextLine();
if(!response.equals("done") ){
toBuy.add(new Item(response, randGen.nextInt(100)));
System.out.println(toBuy);
}
} while(!response.equals("done"));
return toBuy;
}

should work as mentioned in my comment.
Please implement a toString() method in your Item class if not done already.
you should replace your System.out.println as following:
public static ArrayList<Item> purchaseItems()
{
ArrayList<Item> toBuy = new ArrayList<Item>();
String response;
System.out.println("What would you like to purchase? (type \"done\" to end) ");
do {
response = in.nextLine();
if(!response.equals("done") ){
toBuy.add(new Item(response, randGen.nextInt(100)));
}
} while(!response.equals("done"));
for (Item item : toBuy){
System.out.println(item);
}
return toBuy;
}
if this doesn't helps, please share some more code.

Here is fully working example
package stackoverflow;
import java.util.ArrayList;
import java.util.Random;
import java.util.Scanner;
public class Q53837506 {
public static void main(String[] args) {
ArrayList<Item> purchaseItems = purchaseItems();
System.out.println(purchaseItems);
}
public static class Item {
String r;
int v;
public Item(String r, int v) {
super();
this.r = r;
this.v = v;
}
#Override
public String toString() {
return "Item [r=" + r + ", v=" + v + "]";
}
}
static final Random randGen = new Random();
public static ArrayList<Item> purchaseItems() {
ArrayList<Item> toBuy = new ArrayList<Item>();
String response;
System.out.println("What would you like to purchase? (type \"done\" to end) ");
Scanner in = new Scanner(System.in);
do {
response = in.nextLine();
if (!response.equals("done")) {
toBuy.add(new Item(response, randGen.nextInt(100)));
System.out.println(toBuy);
}
} while (!response.equals("done"));
return toBuy;
}
}