How do I parse negative number in parentheses?

In financial application negative numbers are often represented in parentheses. In this post we will learn how we can parse or convert the negative number in parentheses to produce the represented number value. To parse text / string to a number we can use the java.text.DecimalFormat class.

Beside number in parentheses, in this example we also parse negative number that use the minus sign with the currency symbol like $. Let’s jump to the code snippet below:

package org.kodejava.example.text;

import java.text.DecimalFormat;

public class NegativeNumberParse {
    // Pattern for parsing negative number.
    public static final String PATTERN1 = "#,##0.00;(#,##0.00)";
    public static final String PATTERN2 = "$#,##0.00;-$#,##0.00";

    public static void main(String[] args) throws Exception {
        DecimalFormat df = new DecimalFormat(PATTERN1);

        String number1 = "(1000)";
        String number2 = "(1,500.99)";

        System.out.println("number1 = " + df.parse(number1));
        System.out.println("number2 = " + df.parse(number2));

        df = (DecimalFormat) DecimalFormat.getInstance();
        df.applyPattern(PATTERN2);

        String number3 = "-$1000";
        String number4 = "-$1,500.99";

        System.out.println("number3 = " + df.parse(number3));
        System.out.println("number4 = " + df.parse(number4));
    }
}

And here are the results of our code snippet above:

number1 = -1000
number2 = -1500.99
number3 = -1000
number4 = -1500.99

If you need to display or format negative numbers in parentheses you can take a look at the following example How do I display negative number in parentheses?.

How do I display negative number in parentheses?

The code snippet below show us how to display or format negative number in parentheses. We start by defining the number format, the pattern has two parts separated by a semicolon. In the snippet we use the #,##0.00;(#,##0.00) pattern. The pattern after the semicolon will be use to format negative number.

Next we create an instance of DecimalFormat by calling getInstance() method. We apply the the format pattern for the formatter object by calling the applyPattern() method of the DecimalFormat instance. To format the number we simply call the format() method and pass the number we are going to format for display or print out.

package org.kodejava.example.text;

import java.text.DecimalFormat;

public class NegativeNumberFormat {
    // Pattern for formatting negative number.
    public static final String PATTERN1 = "#,##0.00;(#,##0.00)";
    public static final String PATTERN2 = "$#,##0.00;-$#,##0.00";

    public static void main(String[] args) {
        DecimalFormat df = (DecimalFormat) DecimalFormat.getInstance();
        df.applyPattern(PATTERN1);

        // Format using parentheses
        System.out.println("Positive: " + df.format(125));
        System.out.println("Negative: " + df.format(-125));

        // Format using currency symbol and minus sign
        df.applyPattern(PATTERN2);
        System.out.println("Positive: " + df.format(1000));
        System.out.println("Negative: " + df.format(-1000));
    }
}

The result of the code snippet above is:

Positive: 125.00
Negative: (125.00)
Positive: $1,000.00
Negative: -$1,000.00

If you need to parse negative numbers in parentheses to produce the represented number you can see the following example How do I parse negative number in parentheses?.

How do I convert string to Date in GMT timezone?

The following code snippet convert a string representation of a date into a java.util.Date object and the timezone is set to GMT. To parse the string so that the result is in GMT you must set the TimeZone of the DateFormat object into GMT.

package org.kodejava.example.text;

import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.TimeZone;

public class WithTimezoneStringToDate {
    public static void main(String[] args) {
        //
        // Create a DateFormat and set the timezone to GMT.
        //
        DateFormat df = new SimpleDateFormat("E, dd MMM yyyy HH:mm:ss z");
        df.setTimeZone(TimeZone.getTimeZone("GMT"));

        try {
            //
            // Convert string into Date
            //
            Date today = df.parse("Sun, 12 Feb 2012 00:00:00 GMT");
            System.out.println("Today = " + df.format(today));
        } catch (ParseException e) {
            e.printStackTrace();
        }
    }
}

How do I get pattern string of a SimpleDateFormat?

To format a java.util.Date object we use the SimpleDateFormat class. To get back the string pattern that were used to format the date we can use the toPattern() method of this class.

package org.kodejava.example.text;

import java.text.SimpleDateFormat;
import java.util.Date;

public class SimpleDateFormatToPattern {
    public static void main(String[] args) {
        SimpleDateFormat format = new SimpleDateFormat("EEEE, dd/MM/yyyy");

        //
        // Gets a pattern string describing this date format used by the
        // SimpleDateFormat object.
        //
        String pattern = format.toPattern();

        System.out.println("Pattern = " + pattern);
        System.out.println("Date    = " + format.format(new Date()));
    }
}

The result of the program will be as follow:

Pattern = EEEE, dd/MM/yyyy
Date    = Thursday, 16/06/2011

How do I breaks a paragraph into sentences?

This example show you how to use the BreakIterator.getSentenceInstance() to breaks a paragraphs into sentences that composes the paragraph. To get the BreakIterator instance we call the getSentenceInstance() factory method and passes a locale information.

In the count(BreakIterator bi, String source) method we iterates the the break to extract sentences that composes the paragraph which value is stored in the paragraph variable.

package org.kodejava.example.text;

import java.text.BreakIterator;
import java.util.Locale;

public class BreakSentenceExample {
    public static void main(String[] args) {
        String paragraph =
                "Line boundary analysis determines where a text " +
                "string can be broken when line-wrapping. The " +
                "mechanism correctly handles punctuation and " +
                "hyphenated words. Actual line breaking needs to " +
                "also consider the available line width and is " +
                "handled by higher-level software. ";

        BreakIterator iterator =
                BreakIterator.getSentenceInstance(Locale.US);

        int sentences = count(iterator, paragraph);
        System.out.println("Number of sentences: " + sentences);
    }

    private static int count(BreakIterator bi, String source) {
        int counter = 0;
        bi.setText(source);

        int lastIndex = bi.first();
        while (lastIndex != BreakIterator.DONE) {
            int firstIndex = lastIndex;
            lastIndex = bi.next();

            if (lastIndex != BreakIterator.DONE) {
                String sentence = source.substring(firstIndex, lastIndex);
                System.out.println("sentence = " + sentence);
                counter++;
            }
        }
        return counter;
    }
}

Our program will print the following result on the console screen:

sentence = Line boundary analysis determines where a text string can be broken when line-wrapping. 
sentence = The mechanism correctly handles punctuation and hyphenated words. 
sentence = Actual line breaking needs to also consider the available line width and is handled by higher-level software. 
Number of sentences: 3