This example will show how to repeat a string for a given number of times using java, guava and apache commons.
Straight up Java
Char array
@Test
public void repeat_a_string_java_with_char_array() {
int numberOfTimesToRepeat = 3;
String uppityup = new String(new char[numberOfTimesToRepeat]).replace(
"@Test
public void repeat_a_string_java_with_char_array() {
int numberOfTimesToRepeat = 3;
String uppityup = new String(new char[numberOfTimesToRepeat]).replace(
"\0", "up");
assertEquals("upupup", uppityup);
}
", "up");
assertEquals("upupup", uppityup);
}
For loop
With each iteration of a for loop we will append to a StringBuilder a specified number of times repeating a string.
@Test
public void repeat_a_string_java_with_loop() {
int numberOfTimesToRepeat = 3;
StringBuilder uppityup = new StringBuilder();
for (int x = 0; x < numberOfTimesToRepeat; x++) {
uppityup.append("up");
}
assertEquals("upupup", uppityup.toString());
}
Google Guava
Guava Strings.repeat will concatenate an input String a specific number of times.
@Test
public void repeat_a_string_with_guava () {
String uppityup = Strings.repeat("up", 3);
assertEquals("upupup", uppityup);
}
Apache Commons
Apache commons will repeat a String a specified number of times to form a new String.
@Test
public void repeat_a_string_with_apache_commons () {
String uppityup = StringUtils.repeat("up", 3);
assertEquals("upupup", uppityup);
}