null强转机制
2018-09-14 本文已影响43人
alonwang
对于Object,null强转是安全的
class LangTest extends Specification {
def "null cast obj is safe"() {
when:
Object a = null
Integer obj = a
then:
obj == null
}
def "null cast primitive error"() {
when:
Object a = null
//抛出异常的原因是隐式调用了Integer.intValue(),而a为空
int primitive = (Integer) a
then:
def ex = thrown(NullPointerException)
ex.class.name == "java.lang.NullPointerException"
}
}
使用groovy+spock进行单元测试 https://www.cnblogs.com/lovesqcc/p/8647201.html