16f6c0aecf
Inline adoc files when they are included exactly once. Also fix language tags because this inlining gives us better information on what language the code is written in.
61 lines
1.6 KiB
Plaintext
61 lines
1.6 KiB
Plaintext
== Why is this an issue?
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In a multi-threaded situation, un-``++synchronized++`` lazy initialization of static fields could mean that a second thread has access to a half-initialized object while the first thread is still creating it. Allowing such access could cause serious bugs. Instead. the initialization block should be ``++synchronized++``.
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Similarly, updates of such fields should also be ``++synchronized++``.
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This rule raises an issue whenever a lazy static initialization is done on a class with at least one ``++synchronized++`` method, indicating intended usage in multi-threaded applications.
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=== Noncompliant code example
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[source,java]
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----
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private static Properties fPreferences = null;
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private static Properties getPreferences() {
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if (fPreferences == null) {
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fPreferences = new Properties(); // Noncompliant
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fPreferences.put("loading", "true");
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fPreferences.put("filterstack", "true");
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readPreferences();
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}
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return fPreferences;
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}
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}
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----
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=== Compliant solution
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[source,java]
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----
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private static Properties fPreferences = null;
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private static synchronized Properties getPreferences() {
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if (fPreferences == null) {
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fPreferences = new Properties();
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fPreferences.put("loading", "true");
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fPreferences.put("filterstack", "true");
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readPreferences();
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}
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return fPreferences;
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}
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}
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----
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ifdef::env-github,rspecator-view[]
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'''
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== Implementation Specification
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(visible only on this page)
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=== Message
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Synchronize this lazy initialization of 'xxx'
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endif::env-github,rspecator-view[]
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