IdentityCheck
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(Difference between revisions)
| Line 6: | Line 6: | ||
</source> | </source> | ||
<source lang="java"> | <source lang="java"> | ||
| - | public static | + | public static String sayHello() { |
String s1 = "Hello"; | String s1 = "Hello"; | ||
String s2 = " World!"; | String s2 = " World!"; | ||
Current revision
Is there an externally observable difference between following programs?
public static String sayHello() { return "Hello World!"; }
public static String sayHello() { String s1 = "Hello"; String s2 = " World!"; return s1 + s2; }
Of course, there is! Just call the method twice:
assert sayHello() == sayHello();
The first version of the method passes the IdentityCheck test. The second does not. There are also other differences in MemoryAllocations as well as StringsUsedInConstantPool.
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