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.
89 lines
1.7 KiB
Plaintext
89 lines
1.7 KiB
Plaintext
== Why is this an issue?
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The order in which you ``++close++`` database-releated resources is crucial. Close a ``++Connection++`` first, and depending on the database pooling in use, you may no longer be able to truly reach its ``++Statement++``s and ``++ResultSet++``s to close them, even though the calls are made and execute without error.
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=== Noncompliant code example
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[source,java]
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----
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Connection conn = null;
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PreparedStatement ps = null;
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ResultSet rs = null;
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try {
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conn = DriverManager.getConnection(connectionString);
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ps = conn.prepareStatement(query);
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rs = ps.executeQuery();
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// ...
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} finally {
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try {
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if (conn != null) {
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conn.close(); // Noncompliant; close this last
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}
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} catch (Exception e) {};
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try {
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if (ps != null) {
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ps.close();
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}
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} catch (Exception e) {};
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try {
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if (rs != null) {
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rs.close();
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}
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} catch (Exception e) {};
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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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Connection conn = null;
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PreparedStatement ps = null;
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ResultSet rs = null;
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try {
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conn = DriverManager.getConnection(connectionString);
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ps = conn.prepareStatement(query);
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rs = ps.executeQuery();
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// ...
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} finally {
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try {
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if (rs != null) {
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rs.close();
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}
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} catch (Exception e) {};
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try {
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if (ps != null) {
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ps.close();
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}
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} catch (Exception e) {};
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try {
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if (conn != null) {
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conn.close();
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}
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} catch (Exception e) {};
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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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Close this "Connection" last.
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'''
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== Comments And Links
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(visible only on this page)
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=== on 16 Jun 2015, 17:28:24 Ann Campbell wrote:
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CodePro: Close Order
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endif::env-github,rspecator-view[]
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