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n most cases JOINs are faster than sub-queries and it is very rare for a sub-query to be faster.In JOINs RDBMS can create an execution plan that is be... 阅读全文
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Factory methods are used in test-driven development to allow classes to be put under test.For example you have below snippet of code to create and sen... 阅读全文
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## type witnessThe generic method addBox defines one type parameter named U. Generally, a Java compiler can infer the type parameters of a generic met... 阅读全文
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##Target TypesThe Java compiler takes advantage of target typing to infer the type parameters of a generic method invocation. The target type of an ex... 阅读全文
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http://www.javamex.com/tutorials/synchronization_final.shtmlThread-safety with the Java final keywordAs of Java 5, one particular use of the final key... 阅读全文
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The answer is pretty simple -- use it when you actually need something it provides that synchronized doesn't, like timed lock waits, interruptible loc... 阅读全文
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##public finalvoidsetDaemon(booleanon)Marks this thread as either a daemon thread or a user thread. The Java Virtual Machine exits when the only threa... 阅读全文
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# lock across processe.g. Server handles request from different clients, there clients are essentially different processes, they could potentially wri... 阅读全文