Most common formats for String.format(..)

StringFormatTest.java

import org.junit.Test;
import java.util.Date;
import static org.junit.Assert.assertEquals;

public class StringFormatTest {

    @Test public void basicInteger() {
        assertEquals("123456", String.format("%d", 123456));
    }

    @Test public void leftPaddingIntegerWithZeroes() {
        assertEquals("007", String.format("%03d", 7));
    }

    @Test public void integerWithLeadingSpace() {
        assertEquals("  11", String.format("% 4d", 11));
    }

    @Test public void floatWithTwoDecimals() {
        assertEquals("1123.35", String.format("%.2f", 1123.345566));
    }

    @Test public void time() {
        assertEquals("09:26:42", String.format("%tT", 1312180002230L));
    }

    @Test public void date() {
        assertEquals("2011-08-01", String.format("%tF", new Date(1312180002230L)));
    }

    @Test public void dateAndTime() {
        assertEquals("09:26:42.231 2011.08.01", String.format("%1$tH:%1$tM:%1$tS.%1$tL %1$tY.%1$tm.%1$td", 1312180002231L));
    }
}