Plz help!! array of object (for search)

Question

i've got few questions of array of object
1-how to search for a price that is greater than 300 in the array of object
and how to list all of them?
2- how to search for the smallest price in the array of object, and how to list?
can anyone provde a java code for me:P?
but plz don't too complex
coz i'm a learner of javaT_T

Answer 1

_< i still can't understand, and dunno how to change into the code that i needand you guyz help me change it?
/*wirte the driver program which will define and create an array of
objects instantiated from the class WaterBill
Create Accessor and Mutator methods to get/set data from the class.
write code within the driver method to perfrom the following:
a) The final total of funds
b) To search for accounts greater than $300 in the array of objects,
     and list all the customer details
c)To search for the lowest bill in the array of objects, and list
those customer dtails
Class definitions and Objects  using price
import java.text.*;
import javax.swing.JOptionPane;
public class Pre_pb3
     public static void main(String []args)
          int  TTc=0;
          int accNum[]=new int[20];
          String name[]=new String[20], output, stans, display; //stAccNum, stUsage, stTTc;
          double usage[]=new double[20];
          double TTa=0.0;
          double price[]=new double[20];
          char ans;
          double acctG,lowest;
          int i=0;
          waterBill MYwaterBill = new waterBill();
          ans='Y';
          while (!(ans=='N'))
               name=inputName();
               accNum[i]=inputAccNum();
               usage[i]=inputUsage();
               price[i]=calculateAmountOwing(usage[i]);
               TTa=MYwaterBill.TTaPrice(price[i]);
               output=MYwaterBill.outputInfo(name[i], accNum[i], usage[i], price[i]);
               waterBill MYwaterBill2= new waterBill(name[i], accNum[i],usage[i], price[i]);     
               stans=JOptionPane.showInputDialog("Do you wanna continue?, (Y)es, (N)o");
               stans = stans.substring(0, 1);
               stans=stans.toUpperCase();
               ans=stans.charAt(0);
               TTc++;     
          MYwaterBill.outputoutput(TTc, TTa);
          MYwaterBill.findGreat();     //b)
          MYwaterBill.searchDetail();     //c)
          System.exit(0);                                                  
     public static String inputName()
               String name;
               name=JOptionPane.showInputDialog("Enter Name ");
               return name;
     public static int inputAccNum()
          int accNum;
          String stAccNum;
          stAccNum=JOptionPane.showInputDialog("Enter Account Number");
          accNum=Integer.parseInt(stAccNum);
          return accNum;
     public static double inputUsage()
          double usage;
          String stUsage;
          stUsage=JOptionPane.showInputDialog("Enter Water Usage");
          usage=Double.parseDouble(stUsage);
          if (!(usage>=0 && usage<=99999999))
               System.out.println("water useage is invalid");
               System.exit(0);
          return usage;
     public static double calculateAmountOwing(double usage)
          double price=0.0;
          if (usage>=0)
               if (usage<=10000)
                    price=(10000/10)*0.01;
               else if (usage>10000)
                    price=((10000/10)*0.01)+(((usage-10000)/10)*0.02);
          else
                    System.out.println("Error of usage");
               return price;
class waterBill
     private static     int TTc=0 ,accNum=0;
     private static String name, stAccNum, stUsage, stTTc;
     private static String output=" ";
     private static double usage=0.0;
     private static double TTa=0.0;
     private static double price=0.0;
     private static String lowest;
     public waterBill()
          name=" ";
          accNum=0;
          usage=0.0;
          price=0.0;
     public waterBill(String n,int an, double us, double p)
          setName(n);
          setAccNum(an);
          setUsage(us);
          setPrice(p);
     public void setName(String n)
          name=n;
     public void setAccNum(int an)
          accNum=an;
     public void setUsage(double us)
          usage=us;
     public void setPrice(double p)
          price=p;
     public String getName()
          return name;
     public int getAccNum()
          return accNum;
     public double getUsage()
          return usage;
     public double getPrice()
          return price;
     public double TTaPrice(double price)
          TTa=TTa + price;
          return TTa;
     public String outputInfo(String name, int accNum, double usage, double price )
          String output=" ";                         
          output: System.out.println( "Account Number: "+ accNum +
                                   "\nWater Usage: " + usage +
                                   "\nCost Owing: " price
                                   "\nName: "+ name+"\n");
          return output;
     public void outputoutput(int TTc, double TTa)
          display:     System.out.println("Total customer: "+ TTc +
                              "\nTotal amount owing: " + TTa + "\n\n");
     public void findGreat()//search the a/c that is greater than 300.
          //dunno how to do, so i just leave it blank^^"
          public String searchDetail()//search the smallest a/c
          //same...dunno how to doT_T