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sumaraghavi ragha
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Hi all,

Please explin me why
System.out.println(test.contains(42));
System.out.println(test.contains("hihi"));

line one priting true and line 2 false.

Thanks in advance
Suma
 
fred rosenberger
lowercase baba
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for those of use who do not have the book, could you elaborate a little more on the code?
 
Ken Truitt
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...
List<String> test = new ArrayList<String>();
String s = "hi";
test.add("string");
test.add(s);
test.add(s+s);
System.out.println(test.size());
System.out.println(test.contains(42));
System.out.println(test.contains("hihi"));
test.remove("hi");
System.out.println(test.size());
...

size() is called, and result, 3, is printed;
"string", "hi", and "hihi" are added to the list;
contains(42) is called, and the result, false, is printed;
contains("hihi") is called, and the result, true, is printed;
remove("hi") removes middle element;
size() is called and result, 2, is printed.
 
Ram Reddy
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List<String> test = new ArrayList<String>();
System.out.println(test.contains(42));


Here test is a list reference can only contain the Strings.
When what is the use of checking other types ( here 42 Integer) in test by using contains method?
why API written for contains method accepting the object of type 'Object'.
Can any one calrify me about this?

rami
 
It is sorta covered in the JavaRanch Style Guide.
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