Develop Reference

How to split string based on length and space using Java

I'm having a string as following in Java. The length of the string is not known and as an example it will be something like below.
String str = "I love programming. I'm currently working with Java and C++."
For some requirement I want to get first 15 characters. Then 30, 45, 70 next characters. Once the string was split if the name was not meaningful then it should be split from nearest space. For the above example output is as following.
String strSpli1 = "I love "; //Since 'programming' is splitting it was sent to next split
String strSpli2 = "programming. I'm currently ";//Since 'working' is splitting it was sent to next split
String strSpli3 = "working with Java and C++.";
Please help me to achieve this.
Updated answer for anybody having this kind of requirement.
String str = "I love programming. I'm currently working with Java and C++.";
String strSpli1 = "";
String strSpli2 = "";
String strSpli3 = "";
try {
strSpli1 = str.substring(15);
int pos = str.lastIndexOf(" ", 16);
if (pos == -1) {
pos = 15;
}
strSpli1 = str.substring(0, pos);
str = str.substring(pos);
try {
strSpli2 = str.substring(45);
int pos1 = str.lastIndexOf(" ", 46);
if (pos1 == -1) {
pos1 = 45;
}
strSpli2 = str.substring(0, pos1);
str = str.substring(pos1);
try {
strSpli3 = str.substring(70);
int pos2 = str.lastIndexOf(" ", 71);
if (pos2 == -1) {
pos2 = 45;
}
strSpli3 = str.substring(0, pos2);
str = str.substring(pos2);
} catch (Exception ex) {
strSpli3 = str;
}
} catch (Exception ex) {
strSpli2 = str;
}
} catch (Exception ex) {
strSpli1 = str;
}
Thank you

use the 2 parameter version of lastIndexOf() to search for space backwards starting from a given position. Example for the first 15 characters:
int pos = str.lastIndexOf(" ", 16);
if (pos == -1) {
pos = 15;
}
String found = str.substring(0, pos);
str = str.substring(pos+1);
this is missing checks like ensuring the string starts with at least 15 characters, or that pos+1 is valid for given length
suggest having a look at java.text.BreakIterator

why you use so many try catch ? just try this.
public class MyClass {
public static void main(String args[]) {
String str = "I love programming. I'm currently working with Java and C++.";
String strSpli1 = "";
String strSpli2 = "";
String strSpli3 = "";
strSpli1 = str.substring(0, 7);
strSpli2 = str.substring(7, 33);
strSpli3 = str.substring(34, str.length());
System.out.println(strSpli1+"\n");
System.out.println(strSpli2+"\n");
System.out.println(strSpli3+"\n");
}
use substring(start index, end index).

How to Convert Long Data type to double data type in java?

(isPlusClicked || op == '+'){
long result = 0;
String finaldata = edt.getText().toString();
finaldata = finaldata.replace("(", "");
finaldata = finaldata.replace(")", "");
System.out.println(" the string is now ==== "+edt.getText().toString());
String[] total = finaldata.split("\\+");
System.out.println(" *************** "+total[0] + "************** "+total[1]);
System.out.println(" the index in the string array are ..... "+sb.toString());
ArrayList<String> alvalue = new ArrayList<String>();
System.out.println(" the splited number is ==== "+total[0] +" the second number is "+total[1]);
StringBuilder sb1 = new StringBuilder(edt.getText().toString());
int inc = 0;
for(int i = 0;i<sb1.length() ; i++){
char plus = sb1.charAt(i);
if(plus == '+'){
String[] totaly = finaldata.split("\\+| \\++ | \\+++");
if(inc>=1){
System.out.println(" *******inc value with result is ***************** "+result+"?&&&&&& "+inc);
result = result + Long.parseLong(totaly[inc+1]);
}else if(inc<=0){
result = Long.parseLong(totaly[inc]) + Long.parseLong(totaly[inc+1]);
//double myDouble = new Long(result).doubleValue();
System.out.println(" Second value is---- ---- "+totaly[inc+1]);
}
inc = inc +1;
}
edt.setText("");
edt.setText( String.valueOf(result));
}
}
when i am put the value in double
for example:
12345678+32164
than it's give me
ans:5.12377842E8
and when i am try to convert in Long than 122.81+212.122
it give the Zero(0) Answer
so please tell me What m i do? for correct answer

I think you need this, though nothing is evident from your question.
double myDouble = new Long(result).doubleValue();

Words inside square brackes - RegExp

String linkPattern = "\\[[A-Za-z_0-9]+\\]";
String text = "[build]/directory/[something]/[build]/";
RegExp reg = RegExp.compile(linkPattern,"g");
MatchResult matchResult = reg.exec(text);
for (int i = 0; i < matchResult.getGroupCount(); i++) {
System.out.println("group" + i + "=" + matchResult.getGroup(i));
}
I am trying to get all blocks which are encapsulated by squared bracets form a path string:
and I only get group0="[build]" what i want is:
1:"[build]" 2:"[something]" 3:"[build]"
EDIT:
just to be clear words inside the brackets are generated with random text
public static String genText()
{
final int LENGTH = (int)(Math.random()*12)+4;
StringBuffer sb = new StringBuffer();
for (int x = 0; x < LENGTH; x++)
{
sb.append((char)((int)(Math.random() * 26) + 97));
}
String str = sb.toString();
str = str.substring(0,1).toUpperCase() + str.substring(1);
return str;
}
EDIT 2:
JDK works fine, GWT RegExp gives this problem
SOLVED:
Answer from Didier L
String linkPattern = "\\[[A-Za-z_0-9]+\\]";
String result = "";
String text = "[build]/directory/[something]/[build]/";
RegExp reg = RegExp.compile(linkPattern,"g");
MatchResult matchResult = null;
while((matchResult=reg.exec(text)) != null){
if(matchResult.getGroupCount()==1)
System.out.println( matchResult.getGroup(0));
}

I don't know which regex library you are using but using the one from the JDK it would go along the lines of
String linkPattern = "\\[[A-Za-z_0-9]+\\]";
String text = "[build]/directory/[something]/[build]/";
Pattern pat = Pattern.compile(linkPattern);
Matcher mat = pat.matcher(text);
while (mat.find()) {
System.out.println(mat.group());
}
Output:
[build]
[something]
[build]

Try:
String linkPattern = "(\\[[A-Za-z_0-9]+\\])*";
EDIT:
Second try:
String linkPattern = "\\[(\\w+)\\]+"
Third try, see http://rubular.com/r/eyAQ3Vg68N

Java special characters RegEx

I want to achieve following using Regular expression in Java
String[] paramsToReplace = {"email", "address", "phone"};
//input URL string
String ip = "http://www.google.com?name=bob&email=okATtk.com&address=NYC&phone=007";
//output URL string
String op = "http://www.google.com?name=bob&email=&address=&phone=";
The URL can contain special characters like %

Try this expression: (email=)[^&]+ (replace email with your array elements) and replace with the group: input.replaceAll("("+ paramsToReplace[i] + "=)[^&]+", "$1");
String input = "http://www.google.com?name=bob&email=okATtk.com&address=NYC&phone=007";
String output = input;
for( String param : paramsToReplace ) {
output = output.replaceAll("("+ param + "=)[^&]+", "$1");
}

For the example above. you can use split
String[] temp = ip.split("?name=")[1].split("&")[0];
op = temp[0] + "?name=" + temp[1].split("&")[0] +"&email=&address=&phone=";

Something like this?
private final static String REPLACE_REGEX = "=.+\\&";
ip=ip+"&";
for(String param : paramsToReplace) {
ip = ip.replaceAll(param+REPLACE_REGEX, Matcher.quoteReplacement(param+"=&"));
}
P.S. This is only a concept, i didn't compile this code.

You don't need regular expressions to achieve that:
String op = ip;
for (String param : paramsToReplace) {
int start = op.indexOf("?" + param);
if (start < 0)
start = op.indexOf("&" + param);
if (start < 0)
continue;
int end = op.indexOf("&", start + 1);
if (end < 0)
end = op.length();
op = op.substring(0, start + param.length() + 2) + op.substring(end);
}

array in array list

In the input file, there are 2 columns: 1) stem, 2) affixes. In my coding, i recognise each of the columns as tokens i.e. tokens[1] and tokens[2]. However, for tokens[2] the contents are: ng ny nge
stem affixes
---- -------
nyak ng ny nge
my problem here, how can I declare the contents under tokens[2]? Below are my the snippet of the coding:
try {
FileInputStream fstream2 = new FileInputStream(file2);
DataInputStream in2 = new DataInputStream(fstream2);
BufferedReader br2 = new BufferedReader(new InputStreamReader(in2));
String str2 = "";
String affixes = " ";
while ((str2 = br2.readLine()) != null) {
System.out.println("Original:" + str2);
tokens = str2.split("\\s");
if (tokens.length < 4) {
continue;
}
String stem = tokens[1];
System.out.println("stem is: " + stem);
// here is my point
affixes = tokens[3].split(" ");
for (int x=0; x < tokens.length; x++)
System.out.println("affix is: " + affixes);
}
in2.close();
} catch (Exception e) {
System.err.println(e);
} //end of try2

You are using tokens as an array (tokens[1]) and assigning the value of a String.split(" ") to it. So it makes things clear that the type of tokens is a String[] array.
Next,
you are trying to set the value for affixes after splitting tokens[3], we know that tokens[3] is of type String so calling the split function on that string will yield another String[] array.
so the following is wrong because you are creating a String whereas you need String[]
String affixes = " ";
so the correct type should go like this:
String[] affixes = null;
then you can go ahead and assign it an array.
affixes = tokens[3].split(" ");

Are you looking for something like this?
public static void main(String[] args) {
String line = "nyak ng ny nge";
MyObject object = new MyObject(line);
System.out.println("Stem: " + object.stem);
System.out.println("Affixes: ");
for (String affix : object.affixes) {
System.out.println(" " + affix);
}
}
static class MyObject {
public final String stem;
public final String[] affixes;
public MyObject(String line) {
String[] stemSplit = line.split(" +", 2);
stem = stemSplit[0];
affixes = stemSplit[1].split(" +");
}
}
Output:
Stem: nyak
Affixes:
ng
ny
nge