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how do i can list.add int?

BufferedReader in =new BufferedReader(

new FileReader("C:/Documents and Settings/seng/Desktop/testfile/assignment_matrix.txt"));

String text;

while((text = in.readLine()) !=null)

{

List list =new ArrayList();

String[] out = text.split(" ");// Separated by "whitespace"

for(int i = 0; i < out.length; i++)

{

int a = Integer.parseInt(out[i]);

list.add(a);//problem here

Object[] output = list.toArray();

System.out.println(output);

}

may i know how can i list.add int a?

[1060 byte] By [wilfrid100a] at [2007-10-3 3:04:27]

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»» Private constructors

# 1

You can only add Objects to a collection and an int is not an Object but rather a primitve. You can use a "wrapper" class.Use the Integer objectInteger i = new Integer(a);https://java.sun.com/j2se/1.3/docs/api/java/lang/Integer.html

TuringPesta at 2007-7-14 20:54:28 >

top of Java-index,Java Essentials,New To Java...

# 2

Instead ofint a = Integer.parseInt(out[i]);

list.add(a);//problem here

You can just saylist.add(new Integer(out[i]));

It is not very clear why you are doing all this conversion int->Integer (and presumably back

again when you do something with the matrix) and array<->List

You have an array of Strings, why not just create an array of ints?String[] out = text.split(" ");

int intArr[] = new int[out.length];

for(int i = 0; i < out.length; i++) {

intArr[i] = Integer.parseInt(out[i]);

}

pbrockway2a at 2007-7-14 20:54:28 >

# 3

BufferedReader in = new BufferedReader(

new FileReader("C:/Documents and Settings/seng/Desktop/testfile/assignment_matrix.txt"));

String text;

while((text = in.readLine()) != null)

{

String[] out = text.split(" "); // Separated by "whitespace"

List list = new ArrayList();

for(int i = 0; i < out.length; i++)

{

int a = Integer.parseInt(out[i]);

Integer b = new Integer(a);

list.add(b);

Object[] output = list.toArray();

System.out.println(output);

thank you for ur "wrapper"....it's work at all.....

but i get some funny kind of utput, like below:[Ljava.lang.Object;@1ba34f2

[Ljava.lang.Object;@1ea2dfe

[Ljava.lang.Object;@17182c1

[Ljava.lang.Object;@13f5d07

[Ljava.lang.Object;@f4a24a

[Ljava.lang.Object;@cac268

[Ljava.lang.Object;@1a16869

[Ljava.lang.Object;@1cde100

[Ljava.lang.Object;@16f0472

[Ljava.lang.Object;@18d107f

[Ljava.lang.Object;@360be0

[Ljava.lang.Object;@45a877

[Ljava.lang.Object;@1372a1a

[Ljava.lang.Object;@ad3ba4

[Ljava.lang.Object;@126b249

[Ljava.lang.Object;@182f0db

[Ljava.lang.Object;@192d342

[Ljava.lang.Object;@6b97fd

[Ljava.lang.Object;@1c78e57

[Ljava.lang.Object;@5224ee

[Ljava.lang.Object;@f6a746

[Ljava.lang.Object;@15ff48b

[Ljava.lang.Object;@affc70

[Ljava.lang.Object;@1e63e3d

[Ljava.lang.Object;@1004901

[Ljava.lang.Object;@1b90b39

[Ljava.lang.Object;@18fe7c3

[Ljava.lang.Object;@b8df17

[Ljava.lang.Object;@13e8d89

[Ljava.lang.Object;@1be2d65

[Ljava.lang.Object;@9664a1

[Ljava.lang.Object;@1a8c4e7

[Ljava.lang.Object;@1172e08

[Ljava.lang.Object;@cf2c80

[Ljava.lang.Object;@1729854

[Ljava.lang.Object;@6eb38a

[Ljava.lang.Object;@1cd2e5f

[Ljava.lang.Object;@19f953d

[Ljava.lang.Object;@1fee6fc

[Ljava.lang.Object;@1eed786

[Ljava.lang.Object;@187aeca

[Ljava.lang.Object;@e48e1b

[Ljava.lang.Object;@12dacd1

[Ljava.lang.Object;@1ad086a

[Ljava.lang.Object;@10385c1

[Ljava.lang.Object;@42719c

[Ljava.lang.Object;@30c221

[Ljava.lang.Object;@119298d

[Ljava.lang.Object;@f72617

[Ljava.lang.Object;@1bc4459

[Ljava.lang.Object;@12b6651

[Ljava.lang.Object;@4a5ab2

[Ljava.lang.Object;@1888759

[Ljava.lang.Object;@6e1408

[Ljava.lang.Object;@e53108

[Ljava.lang.Object;@f62373

[Ljava.lang.Object;@19189e1

[Ljava.lang.Object;@1f33675

[Ljava.lang.Object;@7c6768

[Ljava.lang.Object;@1690726

[Ljava.lang.Object;@5483cd

[Ljava.lang.Object;@9931f5

[Ljava.lang.Object;@19ee1ac

[Ljava.lang.Object;@1f1fba0

[Ljava.lang.Object;@1befab0

[Ljava.lang.Object;@13c5982

[Ljava.lang.Object;@1186fab

[Ljava.lang.Object;@14b7453

[Ljava.lang.Object;@c21495

[Ljava.lang.Object;@1d5550d

[Ljava.lang.Object;@c2ea3f

[Ljava.lang.Object;@a0dcd9

[Ljava.lang.Object;@186d4c1

[Ljava.lang.Object;@f9f9d8

[Ljava.lang.Object;@1820dda

[Ljava.lang.Object;@15b7986

[Ljava.lang.Object;@87816d

[Ljava.lang.Object;@422ede

[Ljava.lang.Object;@112f614

[Ljava.lang.Object;@1d9dc39

[Ljava.lang.Object;@93dcd

[Ljava.lang.Object;@b89838

[Ljava.lang.Object;@111a3ac

[Ljava.lang.Object;@110b053

[Ljava.lang.Object;@a83b8a

[Ljava.lang.Object;@dd20f6

[Ljava.lang.Object;@19efb05

[Ljava.lang.Object;@723d7c

[Ljava.lang.Object;@22c95b

[Ljava.lang.Object;@1d1acd3

may i know how do i can make sure that my data is correct read?

wilfrid100a at 2007-7-14 20:54:28 >

# 4

you have to cast the Object object back into an Integer. ((Integer)object).toString()

TuringPesta at 2007-7-14 20:54:28 >

# 5

pbrockaway2 is right WTF is this?int a = Integer.parseInt(out);Integer b = new Integer(a);list.add(b);Object[] output = list.toArray();Why are you doing all of that?

TuringPesta at 2007-7-14 20:54:28 >

# 6

And another pressing question is "why did this guy cross-post three times?" http://forum.java.sun.com/thread.jspa?threadID=761457 http://forum.java.sun.com/thread.jspa?threadID=761474 http://forum.java.sun.com/thread.jspa?threadID=761467

myjavasticka at 2007-7-14 20:54:28 >

# 7

this is the 1st time i learn for programming language...i'm sorry if i giving any problem to you all..now i m not very familiar to create a table form, that why i have post alot in the forum....does any1 have simple table coding which can read .txt file?

wilfrid100a at 2007-7-14 20:54:28 >

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