/tutorial/external/Java/example2.e

 1class EXAMPLE2
 2	-- Compilation:
 3	--    compile_to_jvm example2
 4	--    javac ISimple.java
 5	--    javac ASimple.java
 6	-- Execution:
 7	--    java example2
 8	-- This example demonstrates how to read and write Java object class and instance
 9	-- fields from Eiffel.
10
11creation {ANY}
12	make
13
14feature {ANY}
15	make is
16		local
17			a1: POINTER; b: BOOLEAN; i: INTEGER; d: DOUBLE
18		do
19			-- create new ASimple instance
20			a1 := new_ASimple -- verify that it is an instance of ASimple
21			b := instanceof_ASimple(a1)
22			io.put_string("is a1 an instance of ASimple? " + b.to_string + "%N")
23			-- get the instance variable theInteger
24			i := get_theInteger(checkcast_ASimple(a1))
25			io.put_string("value of theInteger: " + i.to_string + "%N")
26			-- set the instance variable theInteger to 13
27			set_theInteger(checkcast_ASimple(a1), 13)
28			-- get the instance variable theInteger
29			i := get_theInteger(checkcast_ASimple(a1))
30			io.put_string("value of theInteger after setting to 13: " + i.to_string + "%N")
31			-- get the class variable theStaticInteger
32			i := get_theStaticInteger
33			io.put_string("value of theStaticInteger: " + i.to_string + "%N")
34			-- set the class variable theStaticInteger to -11
35			set_theStaticInteger(-11)
36			-- get the class variable theStaticInteger
37			i := get_theStaticInteger
38			io.put_string("value of theStaticInteger after setting to -11: " + i.to_string + "%N")
39			-- get the class constant dConstant from ISimple
40			d := get_dConstant
41			io.put_string("value of dConstant: " + d.to_string + "%N")
42		end
43
44feature {ANY} -- externals
45	new_ASimple: POINTER is
46		external "Java class ASimple new ()"
47		end
48
49	checkcast_ASimple (p: POINTER): POINTER is
50		external "Java class ASimple checkcast"
51		end
52
53	instanceof_ASimple (p: POINTER): BOOLEAN is
54		external "Java class ASimple instanceof"
55		end
56
57	get_theStaticInteger: INTEGER is
58		external "Java class ASimple get field static int theStaticInteger"
59		end
60
61	set_theStaticInteger (a: INTEGER) is
62		external "Java class ASimple set field static int theStaticInteger"
63		end
64
65	get_theInteger (p: POINTER): INTEGER is
66		external "Java class ASimple get field int theInteger"
67		end
68
69	set_theInteger (p: POINTER; a: INTEGER) is
70		external "Java class ASimple set field int theInteger"
71		end
72
73	get_dConstant: DOUBLE is
74		external "Java class ISimple get field static double dConstant"
75		end
76
77end -- class EXAMPLE2