> For the complete documentation index, see [llms.txt](https://www.pranaypourkar.co.in/the-programmers-guide/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://www.pranaypourkar.co.in/the-programmers-guide/java/java-basics/java-data-types/specialized-classes/formatter/examples.md).

# Examples

## 1. **Generating Log Messages**

In logging systems, it’s common to format log messages to include timestamps, log levels, and specific message details. The `Formatter` class helps maintain a consistent format.

```java
Formatter formatter = new Formatter();
String logMessage = formatter.format("%1$tF %1$tT - [%2$s] - %3$s", new java.util.Date(), "INFO", "Application started successfully").toString();
System.out.println(logMessage); // 2024-12-27 14:35:20 - [INFO] - Application started successfully
```

## 2. **Creating a Table of Data (Report Generation)**

Formatter is useful in generating tabular data, such as a report for employees, students, or any structured data where alignment is crucial

```java
Formatter formatter = new Formatter();
formatter.format("| %-20s | %-10s | %-10s | %-15s |\n", "Employee", "Department", "Salary", "Joining Date");
formatter.format("| %-20s | %-10s | %-10.2f | %-15s |\n", "Alice", "HR", 75000.50, "2020-01-15");
formatter.format("| %-20s | %-10s | %-10.2f | %-15s |\n", "Bob", "Engineering", 95000.75, "2018-05-20");
formatter.format("| %-20s | %-10s | %-10.2f | %-15s |\n", "Charlie", "Marketing", 80000.00, "2019-11-30");

System.out.println(formatter.toString());
```

Output

```
| Employee             | Department | Salary    | Joining Date    |
| Alice                | HR         | 75000.50  | 2020-01-15      |
| Bob                  | Engineering| 95000.75  | 2018-05-20      |
| Charlie              | Marketing  | 80000.00  | 2019-11-30      |
```

## 3. **Currency and Number Formatting**

Formatter can be used to format financial data according to the required conventions, including currency formatting.

```java
Locale locale = Locale.US;
Formatter formatter = new Formatter(locale);
formatter.format("Price: %.2f", 12345.6789);
System.out.println(formatter.toString());  // $12,345.68

locale = Locale.FRANCE;
formatter = new Formatter(locale);
formatter.format("Price: %.2f", 12345.6789);
System.out.println(formatter.toString());  // 12 345,68 €
```

## **4. Generating a Custom File Output (Exporting Data)**

Formatter can be used to create formatted text files, for instance, when exporting data to CSV or any structured text file. In this case, `Formatter` is used to format and write data to a CSV file.

```java
import java.io.File;
import java.io.IOException;
import java.util.Formatter;

public class CSVExport {
    public static void main(String[] args) throws IOException {
        Formatter formatter = new Formatter(new File("employee_data.csv"));
        formatter.format("Employee Name,Department,Salary,Joining Date\n");
        formatter.format("Alice,HR,75000.50,2020-01-15\n");
        formatter.format("Bob,Engineering,95000.75,2018-05-20\n");
        formatter.format("Charlie,Marketing,80000.00,2019-11-30\n");
        formatter.close();
        System.out.println("File exported successfully!");
    }
}
```

**Output (file `employee_data.csv`):**

```javascript
Employee Name,Department,Salary,Joining Date
Alice,HR,75000.50,2020-01-15
Bob,Engineering,95000.75,2018-05-20
Charlie,Marketing,80000.00,2019-11-30
```

## **5. Locale-specific Date Formatting**

Formatter is useful in generating date/time strings in different formats based on the locale. Here, `Formatter` is used to format dates based on the locale.

```java
import java.util.Formatter;
import java.util.Locale;

public class DateFormatting {
    public static void main(String[] args) {
        Formatter formatter = new Formatter();
        formatter.format("Today's date in US: %1$tm/%1$td/%1$tY", new java.util.Date());
        System.out.println(formatter.toString());  // Today's date in US: 12/27/2024
        
        Locale frenchLocale = Locale.FRANCE;
        formatter = new Formatter(frenchLocale);
        formatter.format("Today's date in France: %1$td/%1$tm/%1$tY", new java.util.Date());
        System.out.println(formatter.toString());  // Today's date in France: 27/12/2024
    }
}
```

## 6. **File Content Formatting for Reporting**

In a reporting system, if we need to format large amounts of data to generate readable reports, `Formatter` can be used. In this example, `Formatter` is used to generate a formatted sales report with headers and data.

```java
import java.util.Formatter;

public class ReportFormatter {
    public static void main(String[] args) {
        Formatter formatter = new Formatter();
        String title = "Monthly Sales Report";
        String header = "| %-15s | %-10s | %-15s | %-15s |\n";
        String data = "| %-15s | %-10d | %-15.2f | %-15s |\n";
        
        // Header
        formatter.format(header, "Product", "Quantity", "Unit Price", "Total Sales");
        
        // Data
        formatter.format(data, "Product A", 100, 15.75, "$1,575.00");
        formatter.format(data, "Product B", 200, 25.00, "$5,000.00");
        
        System.out.println(title);
        System.out.println(formatter.toString());
    }
}
```

```mathematica
Monthly Sales Report
| Product         | Quantity  | Unit Price       | Total Sales      |
| Product A       | 100       | 15.75            | $1,575.00        |
| Product B       | 200       | 25.00            | $5,000.00        |
```

## 7. **Formating Time and Duration**

Formatter can be used to format elapsed time or duration for display purposes, e.g., when displaying download or processing times. In this case, `Formatter` is used to format the duration in a standard `hh:mm:ss` format.

```java
import java.util.Formatter;

public class DurationFormatter {
    public static void main(String[] args) {
        long seconds = 3661; // 1 hour, 1 minute, and 1 second
        Formatter formatter = new Formatter();
        formatter.format("Elapsed Time: %02d:%02d:%02d", 
                         (seconds / 3600), // hours
                         (seconds % 3600) / 60, // minutes
                         seconds % 60); // seconds
        System.out.println(formatter.toString()); //Elapsed Time: 01:01:01
    }
}
```


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://www.pranaypourkar.co.in/the-programmers-guide/java/java-basics/java-data-types/specialized-classes/formatter/examples.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.