For example：
//Test004.javapublicclassTest004 {publicstaticvoidmain(String[] args) {inta =8;intb =8;if(a==b){
System.out.PRintln("a is equal to b.");
}else{
System.out.println("a is not equal to b.");
}/** == and equals
*TheOperator == works a bit different on objects than on primitives.
When we are using objects and want to check if they are equal, the
operator == wiil say if they are the same, if you want to check if
they are logically equal, you should use the equals method on the object.
For example:*/String person_a=newString("gavin");
String person_b=newString("gavin");
String person_c=person_a;
System.out.println(person_a==person_b);//这里会输因为false,//因为person_a和person_b不是一个对象，分配的物理空间的地址不一样System.out.println(person_a.equals(person_b));//这里会输出true,//因为person_a和persion_b的逻辑值一样，都是gavinSystem.out.println(person_a==person_c);//这里会输出true,//因为person_a和person_b实际上是同一个对象}
}
上述代码中的第6行中，a=b就是条件句。在java中，条件句返回的结果必须是boolean类型的值。