次のサンプルコードは、LS2J を使用した LotusScript® 内での Java™ メソッドの呼び出しを例示しています。この例のすぐ次の例ではコードがわずかに変更され、Java と LotusScript の構文に不一致がある状態の処理方法を示しています。
この住宅ローン計算ツールを使用すると、Java プロパティの値を取得して、Java メソッドのいくつかをその名前を使用して LotusScript から直接呼び出すことができます。
public class Mortgage
{
// Java property
public static String F = "Mortgage Calculator";
// Java methods
public double CalculateInterest(float rate, short yr, _
double principal)
{
// This bank doesn't bother with compound interest!
return (rate / 100) * yr * principal;
}
public double CalculateTotal(double principal, _
double interest)
{
return principal + interest;
}
public double CalculateMonthlyPayment(float rate, _
short yr, double principal)
{
double interest = CalculateInterest(rate, yr, _
principal);
double total = CalculateTotal(principal, interest);
return total / (yr * 12);
}
}Uselsx "*javacon"
Dim mySession As JavaSession
Sub Initialize
Dim myClass As JavaClass
Dim myObject As JavaObject
Dim header As String
Dim rate As Single
Dim yr As Integer
Dim principal As Double, interest As Double
Dim total As Double, monthly_payment As Double
Set mySession = New JavaSession()
' Set LS values
rate = 8.5
yr = 30
principal = 200000
Set mySession = New JavaSession()
' Get Java "Mortgage" class
Set myClass = mySession.GetClass("Mortgage")
' Call Java "Mortgage" Constructor
Set myObject = myClass.CreateObject
' Get Java property (can just use the name)
header = myObject.F
' Call Java Methods (can just use the names)
interest = myObject.CalculateInterest(rate, yr, _
principal)
total = myObject.CalculateTotal(principal, interest)
monthly_payment = _
myObject.CalculateMonthlyPayment(rate, yr, principal)
MsgBox { } & header & {
Interest rate: } & rate & {%
Years: } & 30 & {
Principal: $} & principal & {
Interest: $} & Round(interest, 2) & {
Total: $} & Round(total, 2) & {
Monthly payment: $} & Round(monthly_payment, 2)
End Subこの例では、使用されている構文に次のような問題があります。
以上のような種類の構文は、Java では許容されますが、LotusScript では使用できません。「Mortgage2.lss」は、このような状態で LS2J を使用する方法を示しています。最後に JavaError をキャッチする例があります。
public class Mortgage2
{
// Java properties with names that differ only by case
public static String F = "Mortgage Calculator";
public static String f = "from your friendly neighborhood bank";
// Java methods
// Two Java methods with names that differ only by case
public double calculateinterest(float rate, _
short yr, double principal)
{
return rate * yr * principal;
}
public double CalculateInterest(float rate, _
short yr, double principal)
{
return calculateinterest(rate/100, yr, principal);
}
// Method with a long name
public double
CalculateTotal_with_a_method_name_over_40_characters_long
(double principal, double interest)
{
return principal + interest;
}
// Two Java overloaded methods -- differ only by parameter types
public double CalculateMonthlyPayment(double total, short yr)
{
return total / (yr * 12);
}
public double CalculateMonthlyPayment(float rate, short yr, _
double principal)
{
double interest = CalculateInterest(rate, yr, principal);
double total =
CalculateTotal_with_a_method_name_over_40_characters_long
(principal, interest);
return CalculateMonthlyPayment(total, yr);
}
}Uselsx "*javacon"
Dim mySession As JavaSession
Sub Initialize
Dim myClass As JavaClass
Dim myObject As JavaObject
Dim myProperty As JavaProperty
Dim myMethod As JavaMethod
Dim myError As JavaError
Dim header1 As String, header2 As String
Dim rate As Single
Dim yr As Integer
Dim principal As Double, interest As Double
Dim total As Double, monthly_payment As Double
Set mySession = New JavaSession()
' Set LS values
rate = 8.5
yr = 30
principal = 200000
Set mySession = New JavaSession()
Set myClass = mySession.GetClass("Mortgage2;")
' Call "Mortgage2" constructor
Set myObject = myClass.CreateObject
' Use GetProperty()/GetValue() syntax when
' property names differ only by case
Set myProperty = myClass.GetProperty("F")
header1 = myProperty.GetValue()
Set myProperty = myClass.GetProperty("f")
header2 = myProperty.GetValue()
' Use GetMethod()/Invoke() syntax when method
' names differ only by case
Set myMethod = _
myClass.GetMethod("CalculateInterest", "(FSD)D")
interest = myMethod.Invoke(myObject, rate, yr, _
principal)
' or when method name is over 40 characters long
Set myMethod = myClass.GetMethod _
("CalculateTotal_with_a_method_name_over_40_characters_long", _
"(DD)D")
total = myMethod.Invoke(myObject, principal, interest)
' or for overloaded Methods (differing only by parameter type)
Set myMethod = _
myClass.GetMethod("CalculateMonthlyPayment", "(DS)D")
monthly_payment = _
myObject.CalculateMonthlyPayment(total, yr)
MsgBox { } & header1 & {
} & header2 & {
Interest rate: } & rate & {%
Years: } & 30 & {
Principal: $} & principal & {
Interest: $} & Round(interest, 2) & {
Total: $} & Round(total, 2) & {
Monthly payment: $} & Round(monthly_payment, 2)
On Error GoTo errhandler
' Throws "java.lang.NoSuchMethodException"
' when user tries to get a method that doesn't exist
Set myMethod = myClass.GetMethod("CalculateTax", _
"(D)D")
done:
Exit Sub
errhandler:
Set myError = mySession.GetLastJavaError()
MsgBox "JavaError was " & myError.errorMsg
' Clear the Error
mySession.ClearJavaError
Resume done
End Sub