Java库存计划问题 | 码农家园

Java Inventory Program problems

我有两条错误消息，我很难弄清楚它在向我请求什么。错误是：

1
2
3
4
5
6
7
8
9

Desktop\Inventory Program\InventoryPart1.java:93: cannot find symbol
symbol : variable printer
location: class InventoryPart1
System.out.println("Item Number:" + printer.getItemNumber());

Desktop\Inventory Program\InventoryPart1.java:95: cannot find symbol
symbol : variable printer`enter code here`
location: class InventoryPart1
System.out.println("Product Name:" + printer.getProductName());

迄今为止的准则是

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113

import java.text.NumberFormat;
import java.util.locale;
import java.util.Scanner;

class Printer {

private String itemNumber;
private String productName;
private double units;
private double unitPrice;
private double unitsTotal;
//constructor
public Printer (String itemNumber, String productName, double units, double unitsTotal) {
setItemNumber(itemNumber);
setProductName(productName);
setUnits(units);
setUnitPrice(unitPrice);
unitsTotal = units ++;
}

//accessor methods for class variables
public String getItemNumber () {
return itemNumber;
}

public void setItemNumber (String itemNumber) {
this.itemNumber = itemNumber;
}

public String getProductName () {
return productName;
}

public void setProductName (String productName) {
this.productName = productName;
}

public double getUnits () {
return units;
}

public void setUnits (double units) {
this.units = units;
}

public double getUnitPrice () {
return unitPrice;
}

public void setUnitPrice (double unitPrice) {
this.unitPrice = units * unitPrice;
}

public double getUnitsTotal () {
return unitsTotal;
}

public void setUnitsTotal (double unitsTotal) {
this.unitsTotal = units ++;
}

}

public class InventoryPart1 {

public static void main (String args[]) {

int units;

double unitPrice;

double unitsTotal;
unitsTotal = units ++;

double unitsPrice;
unitsPrice = units * unitPrice;

double unitsTotalPrice;
unitsTotalPrice = unitsTotal * unitPrice;

double totalInventory;
totalInventory = unitsTotal * unitsTotalPrice;

NumberFormat nf = NumberFormat. getCurrencyInstance(Locale.US);

//create an instance of the Printer class
Printer epson = new Printer ("Epson579","All In One", 2, 50.99);

//use the methods from class Printer to output the inventory details.
System.out.println("Item Number:" + printer.getItemNumber());

System.out.println("Product Name:" + printer.getProductName());

System.out.print("Number of Units:");
System.out.println(nf.format(units));

System.out.print("Unit Price:");
System.out.println(nf.format(unitPrice));

System.out.print("Units Total:");
System.out.println(nf.format(unitsTotal));

System.out.print("Units Total Price:");
System.out.println(nf.format(unitsTotalPrice));

System.out.print("Total Inventory:");
System.out.println(nf.format(totalInventory));
}

}

抱歉，这是一个新网站，但仍在努力解决输入整个代码的问题，

相关讨论

几个问题…

实例名应该是打印机，而不是epson
单位总数应为静态字段而不是实例变量
要么在使用之前初始化所有局部变量，要么删除它们，因为您可以使用打印机类中的成员方法计算统计信息。
显示时使用打印机类中的所有成员方法而不是局部变量
使用numberFormat.getIntegerInstance将整数格式化为numberFormat.getCurrencyInstance用于格式化货币字段。

您需要重新考虑Units、UnitsTotal、Units Price和Inventory字段。

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77

import java.text.NumberFormat;
import java.util.Locale;

class Printer {

private String itemNumber;
private String productName;
private double units;
private double unitPrice;
private static double unitsTotal;

// constructor
public Printer(String itemNumber, String productName, double units, double unitPrice) {
setItemNumber(itemNumber);
setProductName(productName);
setUnits(units);
setUnitPrice(unitPrice);
unitsTotal += units;
}

// accessor methods for class variables
public String getItemNumber() {
return itemNumber;
}

public void setItemNumber(String itemNumber) {
this.itemNumber = itemNumber;
}

public String getProductName() {
return productName;
}

public void setProductName(String productName) {
this.productName = productName;
}

public double getUnits() {
return units;
}

public void setUnits(double units) {
this.units = units;
}

public double getUnitPrice() {
return unitPrice;
}

public void setUnitPrice(double unitPrice) {
this.unitPrice = unitPrice;
}

public static double getUnitsTotal() {
return unitsTotal;
}
}

public class InventoryPart1 {

public static void main(String args[]) {
NumberFormat nf = NumberFormat.getCurrencyInstance(Locale.US);
NumberFormat inf = NumberFormat.getIntegerInstance(Locale.US);

// create an instance of the Printer class
Printer printer = new Printer("Epson579","All In One", 2, 50.99);

// use the methods from class Printer to output the inventory details.
System.out.println("Item Number :" + printer.getItemNumber());
System.out.println("Product Name :" + printer.getProductName());
System.out.println("Number of Units :" + inf.format(printer.getUnits()));
System.out.println("Unit Price :" + nf.format(printer.getUnitPrice()));
System.out.println("Units Total :" + inf.format(printer.getUnitsTotal()));
System.out.println("Units Total Price:" + nf.format(printer.getUnitPrice() * Printer.getUnitsTotal()));
System.out.println("Total Inventory :" + inf.format(Printer.getUnitsTotal()));
}
}

样品运行：

1
2
3
4
5
6
7

Item Number : Epson579
Product Name : All In One
Number of Units : 2
Unit Price : $50.99
Units Total : 2
Units Total Price: $101.98
Total Inventory : 2