Errors in Map class
Hello Everyone.
Well I working on a program that uses Map class and I have some errors.
They are listed as.
on line 110
Type safety: The method put(Object, Object) belongs to the raw type HashMap. References to
generic type HashMap<K,V> should be parameterized
line 115
pe safety: The expression of type Collection needs unchecked conversion to conform to
Collection<ComputerInvent>
line 123
Type mismatch: cannot convert from Object to Computer_listing
Here is my code is far
import java.io.*;
import java.util.*;
class Computer_listing{
private String id;
private String name;
private Integer harddrive;
private Integer memory;
privatefloat speed;
public Computer_listing(String idx){
id = idx;
}// close the computer_listing loop
/**
* Constructors.
*/
public Computer_listing(String cd, String cn, Integer hd, Integer me,
float sp){
id = cd;
name = cn;
harddrive = hd;
memory = me;
speed = sp;
}// close public EmployeeClass
/*
* accessors make info available
*/
public String getId(){
return id;
}
public String getName(){
return name;
}
public Integer getHardrive(){
return harddrive;
}
public Integer getMemory(){
return memory;
}
publicfloat getSpeed(){
return speed;
}
/*
* Mutator Methods
*/
publicvoid setId(String cd){
id = cd;
}
publicvoid setName(String cn){
name = cn;
}
publicvoid setHarddrive(Integer hd){
harddrive = hd;
}
publicvoid setMemory(Integer me){
memory = me;
}
publicvoid setSpeed(float sp){
speed = sp;
}
}// close class
publicclass ComputerInvent{
publicstaticvoid main(String[] args){
HashMap hs =new HashMap();
Scanner kbd =new Scanner(System.in);
kbd.useDelimiter("\n");
while (true){
String msg =null;
Computer_listing compdb =null;
System.out.println("Enter ComputerID - Stop to end");
msg = kbd.next();
if (msg.equalsIgnoreCase("STOP")){
break;
}else{
compdb =new Computer_listing(msg);
}
System.out.println("Enter Computer Name");
compdb.setId(kbd.next());
System.out.println("Enter HardDrive");
compdb.setHarddrive(kbd.nextInt());
System.out.println("Enter Memory");
compdb.setMemory(kbd.nextInt());
System.out.println("Enter Speed");
compdb.setSpeed(kbd.nextFloat());
// add to data structure
hs.put(msg, hs);//line 110
}// close while loop
System.out.println("Done");
int i = 1;
Collection<ComputerInvent> values = hs.values();//line115
for (ComputerInvent temp : values){
System.out.println("Items are " + i +"" + temp.getClass());
i++;
}// close for loop
System.out.println("Enter ID to find");
String findit = kbd.next();
Computer_listing x =null;
if ((x = hs.get(findit)) !=null){//line 123
System.out.println("Found it");
System.out.println("Name is " + x.getClass());
}else{
System.out.println("Did not find it");
}// close else
}// close public static void
}// close public class ComputerInvent
Can someone please help me in solving this.
thanks
sandyR
[7302 byte] By [
SandyReda] at [2007-11-27 2:11:29]
The code should have thrown hundreds of errors i wonder how u managed with few
import java.io.*;
import java.util.*;
class Computer_listing {
private String id;
private String name;
private Integer harddrive;
private Integer memory;
private float speed;
public Computer_listing(String idx) {
this.id = idx;
}
public Computer_listing(String cd, String cn, Integer hd, Integer me,
float sp) {
this.id = cd;
this.name = cn;
this.harddrive = hd;
this.memory = me;
this.speed = sp;
}
public String getId() {
return this.id;
}
public String getName() {
return this.name;
}
public Integer getHardrive() {
return this.harddrive;
}
public Integer getMemory() {
return this.memory;
}
public float getSpeed() {
return this.speed;
}
public void setId(String cd) {
this.id = cd;
}
public void setName(String cn) {
this.name = cn;
}
public void setHarddrive(Integer hd) {
this.harddrive = hd;
}
public void setMemory(Integer me) {
this.memory = me;
}
public void setSpeed(float sp) {
this.speed = sp;
}
}
public class ComputerInvent{
public static void main(String s[]){
HashMap<String,Computer_listing> hs = new HashMap<String,Computer_listing>();
Scanner kbd = new Scanner(System.in);
kbd.useDelimiter("\n");
while(true){
String msg = null;
Computer_listing compdb = null;
System.out.println("Enter <ComputerID> - Type <Stop> to end");
msg = kbd.next();
if (msg.equalsIgnoreCase("STOP"))
break;
else
compdb = new Computer_listing(msg);
System.out.println("Enter Computer Name:");
compdb.setId(kbd.next());
System.out.println("Enter HardDrive:");
compdb.setHarddrive(kbd.nextInt());
System.out.println("Enter Memory:");
compdb.setMemory(kbd.nextInt());
System.out.println("Enter Clock Speed:");
compdb.setSpeed(kbd.nextFloat());
hs.put(msg,compdb);
}
System.out.println("<Done>");
Collection<Computer_listing> values = hs.values();
int i = 0;
for (Computer_listing temp : values) {
System.out.println("Name["+ i + "]:" + temp.getName());
i++;
}
System.out.println("Enter ID to find");
String findit = kbd.next();
Computer_listing x = null;
if ((x = hs.get(findit)) != null) {
System.out.println("Found it");
System.out.println("Name is " + x.getName());
} else {
System.out.println("Did not find it");
}
}
}
Hope that works :)
Anyways i'd advice you learn basics of using java.util Classes first and then go about using generics if you are a starter.
REGARDS,
RaHuL
Thanks for the help but now I get a scanner error when I run it
The errors above have been fixted but now the scanner is wrong when I run the program
An error will show up on these
error code is.
at java.util.Scanner.next(Scanner.java:1431)
at java.util.Scanner.nextFloat(Scanner.java:2267)
at computerInv.ComputerInvent.main(ComputerInvent.java:128)
System.out.println("Enter HardDrive");// this is line 128
compdb.setHarddrive(kbd.nextInt());
System.out.println("Enter Memory");//if I take out line 128 and 129 I get the same error
compdb.setMemory(kbd.nextInt());
System.out.println("Enter Speed");//like wise on this one
compdb.setSpeed(kbd.nextFloat());
Can you please tell me why and or show me how to correct this.
thanks
