34 lines
884 B
Plaintext
34 lines
884 B
Plaintext
Some implementations of ``++java.sql.ResultSet#getMetaData()++`` suffer from performance issue and should not be called in a loop. Instead, multiple calls in a row should be replaced by a single cached call.
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== Noncompliant Code Example
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[source,java]
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----
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ResultSetMetaData rsmd = rs.getMetaData();
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for (int i=1; i<rsmd.getColumnCount(); i++) {
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System.out.println(rs.getMetaData().getAutoIncrement()); // Noncompliant; "rs.getMetaData()" will be called for each columns
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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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ResultSetMetaData rsmd = rs.getMetaData(); // Compliant; result of "rs.getMetaData()" is cached
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for (int i=1; i<rsmd.getColumnCount(); i++) {
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System.out.println(rsmd.getAutoIncrement());
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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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include::message.adoc[]
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endif::env-github,rspecator-view[]
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