Java基础封装类型的缓存
| 类型 | 缓存范围 |
|---|---|
| Byte | -128-127 |
| Short | -128-127 |
| Integer | -128-127 |
| Long | -128-127 |
| Character | 0-127 |
常见笔试题
public class Main {
public static void main(String[] args) {
//[-128,127]
Integer i1 = 10;
Integer i2 = 10;
System.out.println(i1 == i2); //true
System.out.println(i1.equals(i2)); //true
Integer i3 = -128;
Integer i4 = -128;
System.out.println(i3 == i4); //true
System.out.println(i3.equals(i4)); //true
}
public class Main {
public static void main(String[] args) {
//[-128,127]
Integer i1 = 200;
Integer i2 = 200;
System.out.println(i1 == i2); //false
System.out.println(i1.equals(i2)); //true
Integer i3 = -128;
Integer i4 = -128;
System.out.println(i3 == i4); //true
System.out.println(i3.equals(i4));
//true
}
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