https://codelog.me/en/tags/memory-model/Recent content in Memory Model on Code LogHugoen-USTue, 20 Jan 2015 14:05:51 +0800https://codelog.me/en/posts/java-string-intern/Tue, 20 Jan 2015 14:05:51 +0800https://codelog.me/en/posts/java-string-intern/<p>As you know, calling <code>string.intern()</code> in Java first looks up the corresponding string in the string constant pool; if the string does not exist, it is created in the pool and then returned.</p> <p>The string constant pool is a fixed-size HashMap whose default bucket count is 1009; starting from Java 7u40, this default was increased to 60013. In Java 6, the string constant pool was located in the Perm space, and starting from Java 7 it was moved to the Heap space. Below, we use a test program to look at the memory allocation of the string constant pool under the two different versions, Java 6 and Java 7.</p>