5*6* The cache is initialized on first usage. The size of the cache7* may be controlled by the {@code-XX:AutoBoxCacheMax=} option.8* During VM initialization, java.lang.Integer.IntegerCache.high property9* may be set and saved in the private system properties in the10* sun.misc.VM ...
* The cache is initialized on first usage. The size of the cache * may be controlled by the {@code -XX:AutoBoxCacheMax=} option. * During VM initialization, java.lang.Integer.IntegerCache.high property * may be set and saved in the private system properties in the * sun.misc.VM class...
127);// Maximum array size is Integer.MAX_VALUEh=Math.min(h,Integer.MAX_VALUE-(-low)-1);}catch(NumberFormatExceptionnfe){// If the property cannot be parsed into an int, ignore it.}}high=h;// Load IntegerCache.archivedCache from archive, if possibleCDS.initializeFromArchive(IntegerCac...
* The cache is initialized on first usage. The size of the cache * may be controlled by the {@code -XX:AutoBoxCacheMax=} option. * During VMinitialization, java.lang.Integer.IntegerCache.high property * may be set and saved in the private system properties in the * sun.misc.VM class....
static final Integer[] cache; static Integer[] archivedCache; static { // high value may be configured by property int h = 127; String integerCacheHighPropValue = VM.getSavedProperty("java.lang.Integer.IntegerCache.high"); if (integerCacheHighPropValue != null) { ...
Java中的Integer缓存，即Integer Cache，是Java 5引入的一项性能优化特性。它在内存管理和性能提升上起着关键作用。让我们通过实例来理解：期望的测试结果是前三项比较均为false，后两项为true，因为使用equals()比较对象内容而非引用。然而，实际输出显示只有第一个结果出乎意料，我们来探索其背后的机制。首...
可以猜到JAVA在运行时进行了如下优化调整 Integer x=num;// 优化为Integer x=Integer.valueOf(num); 我们随着源码来到Integr.valueOf方法内 publicstaticIntegervalueOf(inti){if(i>=IntegerCache.low&&i<=IntegerCache.high)returnIntegerCache.cache[i+(-IntegerCache.low)];returnnewInteger(i);} ...
方法/步骤 1 一个Java question，求输出结果 publicclassIntegerTest {publicstaticvoidmain(String[] args) {objPoolTest();}publicstaticvoidobjPoolTest() {Integer i1 = 40;Integer i2 = 40;Integer i3 = 0;Integer i4 = newInteger(40);Integer i5 = newInteger(40);Integer i6 = newInteger(0);...
* The cache is initialized on first usage. The size of the cache * may be controlled by the {@code -XX:AutoBoxCacheMax=<size>} option. * During VM initialization, java.lang.Integer.IntegerCache.high property * may be set and saved in the private system properties in the ...
该类位于 Integer.java 内部,该类会在 static 代码块初始化时加载JVM的配置,如果能够加载到对应的值就使用配置值,否则用默认的 -128到 127的范围初始化缓存数组。 现在回过头来看一开始的代码: image.png 结论: (来自方法注释) This method will always cache values in the range -128 to 127, inclusive, an...