69 lines
1.5 KiB
Plaintext
69 lines
1.5 KiB
Plaintext
Java 7 introduced the try-with-resources statement, which guarantees that the resource in question will be closed. Since the new syntax is closer to bullet-proof, it should be preferred over the older ``++try++``/``++catch++``/``++finally++`` version.
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This rule checks that ``++close++``-able resources are opened in a try-with-resources statement.
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*Note* that this rule is automatically disabled when the project's ``++sonar.java.source++`` is lower than ``++7++``.
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== Noncompliant Code Example
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----
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FileReader fr = null;
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BufferedReader br = null;
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try {
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fr = new FileReader(fileName);
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br = new BufferedReader(fr);
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return br.readLine();
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} catch (...) {
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} finally {
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if (br != null) {
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try {
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br.close();
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} catch(IOException e){...}
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}
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if (fr != null ) {
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try {
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br.close();
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} catch(IOException e){...}
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}
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}
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----
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== Compliant Solution
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----
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try (
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FileReader fr = new FileReader(fileName);
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BufferedReader br = new BufferedReader(fr)
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) {
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return br.readLine();
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}
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catch (...) {}
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----
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or
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----
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try (BufferedReader br =
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new BufferedReader(new FileReader(fileName))) { // no need to name intermediate resources if you don't want to
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return br.readLine();
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}
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catch (...) {}
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----
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== See
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* https://wiki.sei.cmu.edu/confluence/x/6DZGBQ[CERT, ERR54-J.] - Use a try-with-resources statement to safely handle closeable resources
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ifdef::env-github,rspecator-view[]
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'''
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== Comments And Links
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(visible only on this page)
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include::comments-and-links.adoc[]
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endif::env-github,rspecator-view[]
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