I have to print list of objects to a text file with table format. For example, if I have list of Person(has getName,getAge and getAddress methods)objects, the text file should look like as below.
Name Age Address
Abc 20 some address1
Def 30 some address2
I can do this by manually writing some code, where I have to take care of spaces and formatting issues.
I am just curious whether are they APIs or tools to do this formatting work?
import java.util.*;
public class Test {
public static void main(String[] args) {
List<Person> list = new ArrayList<Person>();
list.add(new Person("alpha", "astreet", 12));
list.add(new Person("bravo", "bstreet", 23));
list.add(new Person("charlie", "cstreet", 34));
list.add(new Person("delta", "dstreet", 45));
System.out.println(String.format("%-10s%-10s%-10s", "Name", "Age", "Adress"));
for (Person p : list)
System.out.println(String.format("%-10s%-10s%-10d", p.name, p.addr, p.age));
}
}
class Person {
String name;
String addr;
int age;
public Person(String name, String addr, int age) {
this.name = name;
this.addr = addr;
this.age = age;
}
}
Output:
Name Age Adress
alpha astreet 12
bravo bstreet 23
charlie cstreet 34
delta dstreet 45
Use printf with padded fields to achive column alignments.
PrintWriter.printf to be specific
Library for printing Java objects as Markdown / CSV / HTML table using reflection: https://github.com/mjfryc/mjaron-etudes-java
dependencies {
implementation 'io.github.mjfryc:mjaron-etudes-java:0.2.1'
}
import pl.mjaron.etudes;
class Sample {
void sample() {
Cat[] cats = {cat0, cat1};
Table.render(cats, Cat.class)
.markdown() // or .csv() or .html()
.to(System.out) // Or to StrigBuilder | OutputStream | File.
// Optionally specify Left /Right / Center alignment.
.withAlign(VerticalAlign.Left)
.run(); // Or .runToString() to return it to String.
}
}
Sample Markdown output:
| name | legsCount | lazy | topSpeed |
|------|-----------|-------|----------|
| John | 4 | true | 35.24 |
| Bob | 5 | false | 75.0 |
