[Java] 頭ゼロ削除

StripStartZeroTest.java

import org.apache.commons.lang3.StringUtils;
private String stripStartZero(String source) {
  return StringUtils.stripStart(source, "0");
}

@Test
public void testLeftZeroTrim() {
  assertEquals("1", stripStartZero("001"));
  assertEquals("23", stripStartZero("023"));
  assertEquals("4", stripStartZero("4"));
  assertEquals("", stripStartZero(""));
  assertNull(stripStartZero(null));
}