Why is the size of this vector 1? - java

When I use System.out.println to show the size of a vector after calling the following method then it shows 1 although it should show 2 because the String parameter is "7455573;photo41.png;photo42.png" .
private void getIdClientAndPhotonames(String csvClientPhotos)
{
Vector vListPhotosOfClient = new Vector();
String chainePhotos = "";
String photoName = "";
String photoDirectory = new String(csvClientPhotos.substring(0, csvClientPhotos.indexOf(';')));
chainePhotos = csvClientPhotos.substring(csvClientPhotos.indexOf(';')+1);
chainePhotos = chainePhotos.substring(0, chainePhotos.lastIndexOf(';'));
if (chainePhotos.indexOf(';') == -1)
{
vListPhotosOfClient.addElement(new String(chainePhotos));
}
else // aaa;bbb;...
{
for (int i = 0 ; i < chainePhotos.length() ; i++)
{
if (chainePhotos.charAt(i) == ';')
{
vListPhotosOfClient.addElement(new String(photoName));
photoName = "";
continue;
}
photoName = photoName.concat(String.valueOf(chainePhotos.charAt(i)));
}
}
}
So the vector should contain the two String photo41.png and photo42.png , but when I print the vector content I get only photo41.png.
So what is wrong in my code ?

The answer is not valid for this question anymore, because it has been retagged to java-me. Still true if it was Java (like in the beginning): use String#split if you need to handle csv files.
It's be far easier to split the string:
String[] parts = csvClientPhotos.split(";");
This will give a string array:
{"7455573","photo41.png","photo42.png"}
Then you'd simply copy parts[1] and parts[2] to your vector.

You have two immediate problems.
The first is with your initial manipulation of the string. The two lines:
chainePhotos = csvClientPhotos.substring(csvClientPhotos.indexOf(';')+1);
chainePhotos = chainePhotos.substring(0, chainePhotos.lastIndexOf(';'));
when applied to 7455573;photo41.png;photo42.png will end up giving you photo41.png.
That's because the first line removes everything up to the first ; (7455573;) and the second strips off everything from the final ; onwards (;photo42.png). If your intent is to just get rid of the 7455573; bit, you don't need the second line.
Note that fixing this issue alone will not solve all your ills, you still need one more change.
Even though your input string (to the loop) is the correct photo41.png;photo42.png, you still only add an item to the vector each time you encounter a delimiting ;. There is no such delimiter at the end of that string, meaning that the final item won't be added.
You can fix this by putting the following immediately after the for loop:
if (! photoName.equals(""))
vListPhotosOfClient.addElement(new String(photoName));
which will catch the case of the final name not being terminated with the ;.

These two lines are the problem:
chainePhotos = csvClientPhotos.substring(csvClientPhotos.indexOf(';') + 1);
chainePhotos = chainePhotos.substring(0, chainePhotos.lastIndexOf(';'));
After the first one the chainePhotos contains "photo41.png;photo42.png", but the second one makes it photo41.png - which trigers the if an ends the method with only one element in the vector.
EDITED: what a mess.
I ran it with correct input (as provided by the OP) and made a comment above.
I then fixed it as suggested above, while accidently changing the input to 7455573;photo41.png;photo42.png; which worked, but is probably incorrect and doesn't match the explanation above input-wise.
I wish someone would un-answer this.

You can split the string manually. If the string having the ; symbol means why you can do like this? just do like this,
private void getIdClientAndPhotonames(String csvClientPhotos)
{
Vector vListPhotosOfClient = split(csvClientPhotos);
}
private vector split(String original) {
Vector nodes = new Vector();
String separator = ";";
// Parse nodes into vector
int index = original.indexOf(separator);
while(index>=0) {
nodes.addElement( original.substring(0, index) );
original = original.substring(index+separator.length());
index = original.indexOf(separator);
}
// Get the last node
nodes.addElement( original );
return nodes;
}

Related

Java method not doing what expected. Trying to understand why

Trying to write a java method that will take a string, loop through it and where it finds a vowel (A,E,I,O,U,Y) replace it with the vowel plus "OB".
I've written the below but it isn't working as I'd expect and doesn't seem to be matching the current character in my string with the vowels from my list. (The program compiles and runs so it isn't an issue with not importing necessary bits at the beginning. The input string will always be uppercase and only contain alphas.) I'm struggling to figure out where I'm going wrong.
Can anyone help?
public static String obifyText(String text) {
String[] myList = new String[] {"A","E","I","O","U","Y"};
StringBuilder tempText = new StringBuilder(text);
String obify = "OB";
for (int i = 0; i < text.length() -1 ; i ++ ) {
if ( Arrays.asList(myList).contains(tempText.charAt(i)) ) {
System.out.println(tempText.charAt(i)+" found.");
tempText = tempText.insert((i+1),obify);
}
}
text = tempText.toString();
return text;
}
Don't play with indexes.
Managing with indexes could be difficult when you are dealing with changing the string.
Loop on the chars itself as follows:
public static void main(String[] args){
String[] myList = new String[] {"A","E","I","O","U","Y"};
String text = "AEE";
StringBuilder tempText = new StringBuilder("");
String obify = "OB";
for (char c : text.toCharArray()){
tempText = tempText.append(c);
if ( Arrays.asList(myList).contains(c+"") ) {
System.out.println(c+" found.");
tempText = tempText.append(obify);
}
}
text = tempText.toString();
System.out.println(text);
}
OUTPUT:
A found.
E found.
E found.
AOBEOBEOB
charAt returns a char, but myList stores String elements. An array of Strings can never contain values of char. Your if statement never runs.
You can convert the char value to a string:
Arrays.asList(myList).contains(Character.toString(tempText.charAt(i)))
There's just one more problem with your code.
When the code inserts OB after a vowel, there is a side effect: a new vowel O is created. Your code then tries to insert OB after the new O. This is undesired, right?
To make it not do this, you can loop from the end of the string to the start:
for (int i = text.length() - 1; i >= 0 ; i--) {
If this is not a homework question to practice using StringBuilder or for loops, here's a one liner solution using regex:
return text.replaceAll("([AEIOUY])", "$1OB");
You compare two different types in Arrays.asList(myList).contains(tempText.charAt(i)), Arrays.asList(myList) is a List<String> and tempText.charAt is a char. So the contains check will never result in true.
One possible fix, change myList to Character[]
Character[] myList = new Character[] {'A','E','I','O','U','Y'};
There is another problem with the actual insertion, see Pankaj Singhal answer for a solution to that.

Analyse large String using processing

I have a String which I need to split and add to different arrays.
This is my String
{"locations":[{"latitude":"1.3846519","longitude":"103.763276","startTime":"1422720220292","duration":"0","accuracy":"50.981998443604"},{"latitude":"1.3845814","longitude":"103.7634384","startTime":"1422720520181","duration":"0","accuracy":"55.532001495361"},{"latitude":"1.3844195","longitude":"103.763209","startTime":"1422720820265","duration":"0","accuracy":"34.5"},{"latitude":"1.3844051","longitude":"103.7632272","startTime":"1422721120466","duration":"0","accuracy":"36"},
],"success":1}
The output I want is like this in different arrays.
latitudeArray[] = // String array of latitude values
longitudeArray[] = // String array of longitude values
startTimeArray[] = // String array of start time values
durationArray[] = // String array of duration values
accuracyArray[] = // String array of accuracy values
I am using processing IDE to analyse my data and I tried matchAll() and split() functions but couldn't get it work.
Could you please help me in getting my output? Thanks.
Edit: I managed to extract one latitude value but my method seems very inefficient. How can I do this inside a loop?
String[] locationData = loadStrings("sample.txt");
ArrayList<String> latitudeArray = new ArrayList<String>();
ArrayList<String> longitudeArray = new ArrayList<String>();
ArrayList<String> startTimeArray = new ArrayList<String>();
ArrayList<String> durationArray = new ArrayList<String>();
ArrayList<String> accuracyArray = new ArrayList<String>();
String temp;
int index;
index = locationData[0].indexOf("latitude");
println(index);
temp = locationData[0].substring(index+11);
println(temp);
index = temp.indexOf(",");
println(index);
latitudeArray.add(temp.substring(0,(index-1)));
println(latitudeArray.get(0));
Wasn't sure in what format the loadStrings() method returns, so I just used the initial String you provided.
You're heading in the right direction with the string methods. This code tries to benefit from the single input string. If you split on "latitude", then all the elemets in the array, except for the first one, will have the numbers we're interested on in the begining. E.g.: split("latitude\":\"") gives all the latitudes in the begining:
[0] = {"locations":[{"
[1] = 1.3846519","longitude":"103.763276","startTime":"1422720220292","duration":"0","accuracy":"50.981998443604"},{"
[2] = 1.3845814","longitude":"103.7634384","startTime":"1422720520181","duration":"0","accuracy":"55.532001495361"},{"
[3] = 1.3844195","longitude":"103.763209","startTime":"1422720820265","duration":"0","accuracy":"34.5"},{"
[4] = 1.3844051","longitude":"103.7632272","startTime":"1422721120466","duration":"0","accuracy":"36"}, ],"success":1}
To read the actual numbers, we just need to read until the next quote("). Doing indexOf("\"") will give use the position till which we must read to retrieve that number. So, just perform a substring(0,indexOfQuote) on it to get the value. The repeat again, but this time splitting on "longitude" to get them.
Full program:
public static void main(String[] args) {
final String INPUT = "{\"locations\":["
+ "{\"latitude\":\"1.3846519\",\"longitude\":\"103.763276\",\"startTime\":\"1422720220292\",\"duration\":\"0\",\"accuracy\":\"50.981998443604\"},"
+ "{\"latitude\":\"1.3845814\",\"longitude\":\"103.7634384\",\"startTime\":\"1422720520181\",\"duration\":\"0\",\"accuracy\":\"55.532001495361\"},"
+ "{\"latitude\":\"1.3844195\",\"longitude\":\"103.763209\",\"startTime\":\"1422720820265\",\"duration\":\"0\",\"accuracy\":\"34.5\"},"
+ "{\"latitude\":\"1.3844051\",\"longitude\":\"103.7632272\",\"startTime\":\"1422721120466\",\"duration\":\"0\",\"accuracy\":\"36\"},"
+ " ],\"success\":1}";
String latitudeArray[] = splitAndCollect("latitude", INPUT);
String longitudeArray[] = splitAndCollect("longitude", INPUT);
String startTimeArray[] = splitAndCollect("startTime", INPUT);
String durationArray[] = splitAndCollect("duration", INPUT);
String accuracyArray[] = splitAndCollect("accuracy", INPUT);
System.out.println("Done");
}
private static String[] splitAndCollect(String string, String input) {
final String COLON = "\":\"";
String[] split = input.split(string + COLON);
String[] output = new String[split.length - 1];
for (int i = 0; i < output.length; i++)
// Using [i+1] - since split[0] contains "locations".
// Subsequent splits will have the numbers needed.
output[i] = split[i + 1].substring(0, split[i + 1].indexOf("\""));
System.out.println(string + "\n" + Arrays.toString(output));
return output;
}
If you can preprocess the file to csv. file using simple shell script, then do string processing in java, I think you can get better performance. For csv. file processing in Java, refer http://www.mkyong.com/java/how-to-read-and-parse-csv-file-in-java/ (This blog contains simple sample).
If you do some preprocessing step (even in Java) before parsing, you can get all the values to those string arrays simply with one loop. You can use method suggested by Vineet using single loop. So with preprocessing step overall loop count becomes 2.
Thanks,
Mili
It seems that you have data in JSON format. The way you are trying to get data from the is quite difficult (but doable). You can try JSON parser . Its easy to learn and use. You can find one example here.

Comparing arrays

I have String Array of a good couple hundred lines of code. I have two other String Arrays, one with values I want to replace, and the other with the value I want it to replace to. I need to go through each line of the original code and check each line if it contains anything that I need to replace, and if it does, replace it. I want to replace it to a totally different String Array, so that the original is still left unchanged. This is what I have, but it's not exactly working.
for(int i=0; i<originalCode.length; i++) {
if( originalCode[i].contains("| "+listOfThingsToReplace[i]) ) {
newCode[i]=originalCode[i].replaceAll(("| "+listOfThingsToReplace[i]), ("| "+listOfReplacingThings[i]));
}
}
Obviously I need more counting variables somewhere (especially because originalCode.length !=listOfThingsToReplace.length), but I can't figure out where. Would I need more for loops? I tired doing that... but "Exception in thread "main" java.lang.OutOfMemoryError: Java heap space"... Any help please?
I think this should do the trick if I'm understanding the problem correctly
// New Code Array
String[] newCode = new String[originalCode.length];
for (int i=0; i<originalCode.length; i++) {
// New Code Line
String newCodeLine = originalCode[i];
// Iterate through all words that need to be replaced
for (int j=0; j<listOfThingsToReplace.length; j++) {
// String to replace
String strToReplace = listOfThingsToReplace[j];
// String to replace with
String strToReplaceWith = (j >= listOfReplacingThings.length) ? "" : listOfReplacingStrings[j];
// If there is a string to replace with
if (strToReplaceWith != "") {
// then replace all instances of that string
newCodeLine = newCodeLine.replaceAll(strToReplace, strToReplaceWith);
}
}
// Assign the new code line to our new code array
newCode[i] = newCodeLine;
}

Splitting a line and filling an array skipping blank values in Java

I have an array of line, which is somewhat like below
Here's example:
A-NUMBER ROUTINF ACO AO L MISCELL
0-0 0 1-20
0-00
0-01 FDS 3-20
0-02 6 7 3-20
0-03 4 3-20
1-0 F=PRE
ANT=3
NAPI=1
1-1 F=PRE
ANT=3
I need to parse the line according to column by skipping the column which has blank values and create a new line like below
ANUM = 0-0, ACO=0, L=1-20;
ANUM = 0-00;
ANUM = 0-01, ROUTINF=FDS, L=3-20;
ANUM = 0-02, ACO=6, AO=7, L=3-20;
ANUM = 0-03, AO=4,L=3-20;
ANUM = 1-0, F=PRE, ANT=3, NAPI=1;
ANUM = 1-1, F=PRE, ANT=3;
I can split the line but my code can't remember which column the value belongs to and when to skip the values.
String[] splitted = null;
for (Integer i = 0; i < lines.size(); i++) {
splitted = lines.get(i).split("\\s+");
for(String str : splitted)
if(!(splitted.length == 1)){
anum = splitted[0];
routinf = splitted[1];
aco = splitted[2];
ao = splitted[3];
l = splitted[4];
}else {
miscell = splitted[0];
}
}
The columns in your file seems to be of fixed length (I don't see any other way to distinguish each column). If that is the case then I would recommend using substring(srat, end) instead of split.
Create a class to hold one single record.
class Record {
String aNumber,
List<String> routingf, aco, ao, l, miscell;
public Record(String aNumber) {
this.aNumber = aNumber;
this.routingf = new ArrayList<>();
// init other lists like above ...
}
public void addRoutingf(String routingf) {
// add only of not null and is not empty trimmed
if(routingf != null && routiingf.trim().length() > 0) {
this.routingf.add(routiingf);
}
}
// implement add-methods for other lists like above ...
}
While parsing each line remember the last created record. If in the actual line A-NUMBER is empty then use the last created record to store the values, otherwise create a new record and remember it as last/actual so you can use it for the upcoming lines if necessary.
Save all record in a list
List<Record> records = new ArrayList<>();
What is the common separator? Just split on that... Your + at the moment will consume any amount of white space. \s{1,4} wil limit it to between 1 and 4 characters. Find the right numbers for your data.
if your input time use one space char (for instance tab) between columns your code is almost OK
String[] splitted = null;
for (Integer i = 0; i < lines.size(); i++) {
splitted = lines.get(i).split("\\s");
if(!(splitted.length == 1)){
anum = splitted[0];
routinf = splitted[1];
aco = splitted[2];
ao = splitted[3];
l = splitted[4];
}else {
miscell = splitted[0];
}
}
//print only not empty fields
pls note removing of unnecessary for loop and change of split character to \s from \s+
Just a thought, but you could also experiment if it helps to keep the whitespaces in the result for defining which column it belongs to.
lines.get(i).split(yourDelimiter, -1);
Its hard to tell if this helps without knowing what exactly your origin files are looking like, but you could give it a try.
e.g. if the values are always at a certain point in the splitted string with whitespaces, you could easily tell which column it belongs to and extract them.

java: while loop breaks

This loop breaks if uncomment 2 commented string, cannot figure out why it happens, help plz:
private static String findAll(String cell, ArrayList<String> hrange, ArrayList<String> vrange, List<String> cellrange, Integer cycle){
cellrange.add(cell);
String color = XldocReader.xlCells.get(cell);
String[] chkeys = cell.split("\\$");
String chLetter = chkeys[1];
Integer chNumber = Integer.parseInt(chkeys[2]);
boolean rcnext = false;
boolean rcprev = false;
Iterator<String> ite = hrange.iterator();
while ( ite.hasNext() ) {
String candidate = ite.next();
String value = XldocReader.xlCells.get(candidate);
String[] ckeys = candidate.split("\\$");
String cLetter = ckeys[1];
int n = getKeyByValue(chLetter);
String next = cell.replaceAll(chLetter+"", columns.get(n+1) +"");
String cnext = XldocReader.xlCells.get(next);
String prev = cell.replaceAll(chLetter+"", columns.get(n-1) +"");
String cprev = XldocReader.xlCells.get(prev);
//rcnext = cnext.equals(color);
//rcprev = cprev.equals(color);
...
}
return cellrange.toString();
}
it should find equals strings and run recursively check again but on first check it's breaks and nothing check more...
I would make the loop
for(String candidate : hrange) {
}
And I would step through the code in a debugger to see exactly what it is doing as I suspect you program isn't doing what you think it is.
What do you mean by breaks? What is the Exception and on which line does it occur? Does it match what you see in the debugger?
I suspect the problem is in the code you have labelled as ...
Can you give us more info? What the error is? How it breaks? etc. Also, print out the results of color and cnext, cprev right before it breaks.
My guess is those are not legit strings. And you are trying to run an equals method on something that is not a legit string.

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