Showing 716 of 716 total issues
Use already-defined constant 'RUN_RESULTS_XML' instead of duplicating its value here. Open
private final String[] excludedFilenames = new String[] { "run_results.xml", "run_results.html", "diffcompare",
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Duplicated string literals make the process of refactoring error-prone, since you must be sure to update all occurrences.
On the other hand, constants can be referenced from many places, but only need to be updated in a single place.
Noncompliant Code Example
With the default threshold of 3:
public void run() { prepare("action1"); // Noncompliant - "action1" is duplicated 3 times execute("action1"); release("action1"); } @SuppressWarning("all") // Compliant - annotations are excluded private void method1() { /* ... */ } @SuppressWarning("all") private void method2() { /* ... */ } public String method3(String a) { System.out.println("'" + a + "'"); // Compliant - literal "'" has less than 5 characters and is excluded return ""; // Compliant - literal "" has less than 5 characters and is excluded }
Compliant Solution
private static final String ACTION_1 = "action1"; // Compliant public void run() { prepare(ACTION_1); // Compliant execute(ACTION_1); release(ACTION_1); }
Exceptions
To prevent generating some false-positives, literals having less than 5 characters are excluded.
Add a private constructor to hide the implicit public one. Open
public class Base64Encoder {
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Utility classes, which are collections of static
members, are not meant to be instantiated. Even abstract utility classes, which can
be extended, should not have public constructors.
Java adds an implicit public constructor to every class which does not define at least one explicitly. Hence, at least one non-public constructor should be defined.
Noncompliant Code Example
class StringUtils { // Noncompliant public static String concatenate(String s1, String s2) { return s1 + s2; } }
Compliant Solution
class StringUtils { // Compliant private StringUtils() { throw new IllegalStateException("Utility class"); } public static String concatenate(String s1, String s2) { return s1 + s2; } }
Exceptions
When class contains public static void main(String[] args)
method it is not considered as utility class and will be ignored by this
rule.
Remove this unused method parameter "postRunAction". Open
String postRunAction,
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Unused parameters are misleading. Whatever the values passed to such parameters, the behavior will be the same.
Noncompliant Code Example
void doSomething(int a, int b) { // "b" is unused compute(a); }
Compliant Solution
void doSomething(int a) { compute(a); }
Exceptions
The rule will not raise issues for unused parameters:
- that are annotated with
@javax.enterprise.event.Observes
- in overrides and implementation methods
- in interface
default
methods - in non-private methods that only
throw
or that have empty bodies - in annotated methods, unless the annotation is
@SuppressWarning("unchecked")
or@SuppressWarning("rawtypes")
, in which case the annotation will be ignored - in overridable methods (non-final, or not member of a final class, non-static, non-private), if the parameter is documented with a proper javadoc.
@Override void doSomething(int a, int b) { // no issue reported on b compute(a); } public void foo(String s) { // designed to be extended but noop in standard case } protected void bar(String s) { //open-closed principle } public void qix(String s) { throw new UnsupportedOperationException("This method should be implemented in subclasses"); } /** * @param s This string may be use for further computation in overriding classes */ protected void foobar(int a, String s) { // no issue, method is overridable and unused parameter has proper javadoc compute(a); }
See
- CERT, MSC12-C. - Detect and remove code that has no effect or is never executed
Catch Exception instead of Throwable. Open
} catch (Throwable cause) {
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Throwable
is the superclass of all errors and exceptions in Java. Error
is the superclass of all errors, which are not
meant to be caught by applications.
Catching either Throwable
or Error
will also catch OutOfMemoryError
and InternalError
, from
which an application should not attempt to recover.
Noncompliant Code Example
try { /* ... */ } catch (Throwable t) { /* ... */ } try { /* ... */ } catch (Error e) { /* ... */ }
Compliant Solution
try { /* ... */ } catch (RuntimeException e) { /* ... */ } try { /* ... */ } catch (MyException e) { /* ... */ }
See
- MITRE, CWE-396 - Declaration of Catch for Generic Exception
- C++ Core Guidelines E.14 - Use purpose-designed user-defined types as exceptions (not built-in types)
Either re-interrupt this method or rethrow the "InterruptedException" that can be caught here. Open
} catch (InterruptedException e) {
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InterruptedExceptions
should never be ignored in the code, and simply logging the exception counts in this case as "ignoring". The
throwing of the InterruptedException
clears the interrupted state of the Thread, so if the exception is not handled properly the fact
that the thread was interrupted will be lost. Instead, InterruptedExceptions
should either be rethrown - immediately or after cleaning up
the method's state - or the thread should be re-interrupted by calling Thread.interrupt()
even if this is supposed to be a
single-threaded application. Any other course of action risks delaying thread shutdown and loses the information that the thread was interrupted -
probably without finishing its task.
Similarly, the ThreadDeath
exception should also be propagated. According to its JavaDoc:
If
ThreadDeath
is caught by a method, it is important that it be rethrown so that the thread actually dies.
Noncompliant Code Example
public void run () { try { while (true) { // do stuff } }catch (InterruptedException e) { // Noncompliant; logging is not enough LOGGER.log(Level.WARN, "Interrupted!", e); } }
Compliant Solution
public void run () { try { while (true) { // do stuff } }catch (InterruptedException e) { LOGGER.log(Level.WARN, "Interrupted!", e); // Restore interrupted state... Thread.currentThread().interrupt(); } }
See
- MITRE, CWE-391 - Unchecked Error Condition
- Dealing with InterruptedException
Catch Exception instead of Throwable. Open
} catch (Throwable e) {
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Throwable
is the superclass of all errors and exceptions in Java. Error
is the superclass of all errors, which are not
meant to be caught by applications.
Catching either Throwable
or Error
will also catch OutOfMemoryError
and InternalError
, from
which an application should not attempt to recover.
Noncompliant Code Example
try { /* ... */ } catch (Throwable t) { /* ... */ } try { /* ... */ } catch (Error e) { /* ... */ }
Compliant Solution
try { /* ... */ } catch (RuntimeException e) { /* ... */ } try { /* ... */ } catch (MyException e) { /* ... */ }
See
- MITRE, CWE-396 - Declaration of Catch for Generic Exception
- C++ Core Guidelines E.14 - Use purpose-designed user-defined types as exceptions (not built-in types)
Add a private constructor to hide the implicit public one. Open
public class AUTEnvironmentResources {
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Utility classes, which are collections of static
members, are not meant to be instantiated. Even abstract utility classes, which can
be extended, should not have public constructors.
Java adds an implicit public constructor to every class which does not define at least one explicitly. Hence, at least one non-public constructor should be defined.
Noncompliant Code Example
class StringUtils { // Noncompliant public static String concatenate(String s1, String s2) { return s1 + s2; } }
Compliant Solution
class StringUtils { // Compliant private StringUtils() { throw new IllegalStateException("Utility class"); } public static String concatenate(String s1, String s2) { return s1 + s2; } }
Exceptions
When class contains public static void main(String[] args)
method it is not considered as utility class and will be ignored by this
rule.
Define a constant instead of duplicating this literal "build '" 6 times. Open
logger.error("build '" + jobId + " #" + buildId + "' not found");
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Duplicated string literals make the process of refactoring error-prone, since you must be sure to update all occurrences.
On the other hand, constants can be referenced from many places, but only need to be updated in a single place.
Noncompliant Code Example
With the default threshold of 3:
public void run() { prepare("action1"); // Noncompliant - "action1" is duplicated 3 times execute("action1"); release("action1"); } @SuppressWarning("all") // Compliant - annotations are excluded private void method1() { /* ... */ } @SuppressWarning("all") private void method2() { /* ... */ } public String method3(String a) { System.out.println("'" + a + "'"); // Compliant - literal "'" has less than 5 characters and is excluded return ""; // Compliant - literal "" has less than 5 characters and is excluded }
Compliant Solution
private static final String ACTION_1 = "action1"; // Compliant public void run() { prepare(ACTION_1); // Compliant execute(ACTION_1); release(ACTION_1); }
Exceptions
To prevent generating some false-positives, literals having less than 5 characters are excluded.
Either re-interrupt this method or rethrow the "InterruptedException" that can be caught here. Open
} catch (IOException | InterruptedException e) {
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InterruptedExceptions
should never be ignored in the code, and simply logging the exception counts in this case as "ignoring". The
throwing of the InterruptedException
clears the interrupted state of the Thread, so if the exception is not handled properly the fact
that the thread was interrupted will be lost. Instead, InterruptedExceptions
should either be rethrown - immediately or after cleaning up
the method's state - or the thread should be re-interrupted by calling Thread.interrupt()
even if this is supposed to be a
single-threaded application. Any other course of action risks delaying thread shutdown and loses the information that the thread was interrupted -
probably without finishing its task.
Similarly, the ThreadDeath
exception should also be propagated. According to its JavaDoc:
If
ThreadDeath
is caught by a method, it is important that it be rethrown so that the thread actually dies.
Noncompliant Code Example
public void run () { try { while (true) { // do stuff } }catch (InterruptedException e) { // Noncompliant; logging is not enough LOGGER.log(Level.WARN, "Interrupted!", e); } }
Compliant Solution
public void run () { try { while (true) { // do stuff } }catch (InterruptedException e) { LOGGER.log(Level.WARN, "Interrupted!", e); // Restore interrupted state... Thread.currentThread().interrupt(); } }
See
- MITRE, CWE-391 - Unchecked Error Condition
- Dealing with InterruptedException
Either re-interrupt this method or rethrow the "InterruptedException" that can be caught here. Open
} catch (IOException | InterruptedException e) {
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InterruptedExceptions
should never be ignored in the code, and simply logging the exception counts in this case as "ignoring". The
throwing of the InterruptedException
clears the interrupted state of the Thread, so if the exception is not handled properly the fact
that the thread was interrupted will be lost. Instead, InterruptedExceptions
should either be rethrown - immediately or after cleaning up
the method's state - or the thread should be re-interrupted by calling Thread.interrupt()
even if this is supposed to be a
single-threaded application. Any other course of action risks delaying thread shutdown and loses the information that the thread was interrupted -
probably without finishing its task.
Similarly, the ThreadDeath
exception should also be propagated. According to its JavaDoc:
If
ThreadDeath
is caught by a method, it is important that it be rethrown so that the thread actually dies.
Noncompliant Code Example
public void run () { try { while (true) { // do stuff } }catch (InterruptedException e) { // Noncompliant; logging is not enough LOGGER.log(Level.WARN, "Interrupted!", e); } }
Compliant Solution
public void run () { try { while (true) { // do stuff } }catch (InterruptedException e) { LOGGER.log(Level.WARN, "Interrupted!", e); // Restore interrupted state... Thread.currentThread().interrupt(); } }
See
- MITRE, CWE-391 - Unchecked Error Condition
- Dealing with InterruptedException
Catch Exception instead of Throwable. Open
} catch (Throwable e) {
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Throwable
is the superclass of all errors and exceptions in Java. Error
is the superclass of all errors, which are not
meant to be caught by applications.
Catching either Throwable
or Error
will also catch OutOfMemoryError
and InternalError
, from
which an application should not attempt to recover.
Noncompliant Code Example
try { /* ... */ } catch (Throwable t) { /* ... */ } try { /* ... */ } catch (Error e) { /* ... */ }
Compliant Solution
try { /* ... */ } catch (RuntimeException e) { /* ... */ } try { /* ... */ } catch (MyException e) { /* ... */ }
See
- MITRE, CWE-396 - Declaration of Catch for Generic Exception
- C++ Core Guidelines E.14 - Use purpose-designed user-defined types as exceptions (not built-in types)
Refactor this method to reduce its Cognitive Complexity from 27 to the 15 allowed. Open
private boolean isInternal(Run r) {
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Cognitive Complexity is a measure of how hard the control flow of a method is to understand. Methods with high Cognitive Complexity will be difficult to maintain.
See
Merge this if statement with the enclosing one. Open
if ((listItems.size() != 1) || (!listItems.get(0).getName().toLowerCase().equals(term.toLowerCase()))) {
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Merging collapsible if
statements increases the code's readability.
Noncompliant Code Example
if (file != null) { if (file.isFile() || file.isDirectory()) { /* ... */ } }
Compliant Solution
if (file != null && isFileOrDirectory(file)) { /* ... */ } private static boolean isFileOrDirectory(File file) { return file.isFile() || file.isDirectory(); }
Define a constant instead of duplicating this literal "projectName" 3 times. Open
String projectName = getFieldValue(fprPublisher, "projectName");
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Duplicated string literals make the process of refactoring error-prone, since you must be sure to update all occurrences.
On the other hand, constants can be referenced from many places, but only need to be updated in a single place.
Noncompliant Code Example
With the default threshold of 3:
public void run() { prepare("action1"); // Noncompliant - "action1" is duplicated 3 times execute("action1"); release("action1"); } @SuppressWarning("all") // Compliant - annotations are excluded private void method1() { /* ... */ } @SuppressWarning("all") private void method2() { /* ... */ } public String method3(String a) { System.out.println("'" + a + "'"); // Compliant - literal "'" has less than 5 characters and is excluded return ""; // Compliant - literal "" has less than 5 characters and is excluded }
Compliant Solution
private static final String ACTION_1 = "action1"; // Compliant public void run() { prepare(ACTION_1); // Compliant execute(ACTION_1); release(ACTION_1); }
Exceptions
To prevent generating some false-positives, literals having less than 5 characters are excluded.
This accessibility update should be removed. Open
field.setAccessible(true);
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This rule raises an issue when reflection is used to change the visibility of a class, method or field, and when it is used to directly update a field value. Altering or bypassing the accessibility of classes, methods, or fields violates the encapsulation principle and could lead to run-time errors.
Noncompliant Code Example
public void makeItPublic(String methodName) throws NoSuchMethodException { this.getClass().getMethod(methodName).setAccessible(true); // Noncompliant } public void setItAnyway(String fieldName, int value) { this.getClass().getDeclaredField(fieldName).setInt(this, value); // Noncompliant; bypasses controls in setter }
See
- CERT, SEC05-J. - Do not use reflection to increase accessibility of classes, methods, or fields
Extract this nested try block into a separate method. Open
try {
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Nesting try
/catch
blocks severely impacts the readability of source code because it makes it too difficult to understand
which block will catch which exception.
Either re-interrupt this method or rethrow the "InterruptedException" that can be caught here. Open
} catch (InterruptedException ex) {
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InterruptedExceptions
should never be ignored in the code, and simply logging the exception counts in this case as "ignoring". The
throwing of the InterruptedException
clears the interrupted state of the Thread, so if the exception is not handled properly the fact
that the thread was interrupted will be lost. Instead, InterruptedExceptions
should either be rethrown - immediately or after cleaning up
the method's state - or the thread should be re-interrupted by calling Thread.interrupt()
even if this is supposed to be a
single-threaded application. Any other course of action risks delaying thread shutdown and loses the information that the thread was interrupted -
probably without finishing its task.
Similarly, the ThreadDeath
exception should also be propagated. According to its JavaDoc:
If
ThreadDeath
is caught by a method, it is important that it be rethrown so that the thread actually dies.
Noncompliant Code Example
public void run () { try { while (true) { // do stuff } }catch (InterruptedException e) { // Noncompliant; logging is not enough LOGGER.log(Level.WARN, "Interrupted!", e); } }
Compliant Solution
public void run () { try { while (true) { // do stuff } }catch (InterruptedException e) { LOGGER.log(Level.WARN, "Interrupted!", e); // Restore interrupted state... Thread.currentThread().interrupt(); } }
See
- MITRE, CWE-391 - Unchecked Error Condition
- Dealing with InterruptedException
Remove this unused method parameter "run". Open
private SCMData extractSCMData(Run run, SCM scm, List<ChangeLogSet<? extends ChangeLogSet.Entry>> changes) {
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Unused parameters are misleading. Whatever the values passed to such parameters, the behavior will be the same.
Noncompliant Code Example
void doSomething(int a, int b) { // "b" is unused compute(a); }
Compliant Solution
void doSomething(int a) { compute(a); }
Exceptions
The rule will not raise issues for unused parameters:
- that are annotated with
@javax.enterprise.event.Observes
- in overrides and implementation methods
- in interface
default
methods - in non-private methods that only
throw
or that have empty bodies - in annotated methods, unless the annotation is
@SuppressWarning("unchecked")
or@SuppressWarning("rawtypes")
, in which case the annotation will be ignored - in overridable methods (non-final, or not member of a final class, non-static, non-private), if the parameter is documented with a proper javadoc.
@Override void doSomething(int a, int b) { // no issue reported on b compute(a); } public void foo(String s) { // designed to be extended but noop in standard case } protected void bar(String s) { //open-closed principle } public void qix(String s) { throw new UnsupportedOperationException("This method should be implemented in subclasses"); } /** * @param s This string may be use for further computation in overriding classes */ protected void foobar(int a, String s) { // no issue, method is overridable and unused parameter has proper javadoc compute(a); }
See
- CERT, MSC12-C. - Detect and remove code that has no effect or is never executed
Remove this useless assignment to local variable "suiteId". Open
String suiteId = getParameterValueIfExist(parametersAction, SdkConstants.JobParameters.SUITE_ID_PARAMETER_NAME);
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A dead store happens when a local variable is assigned a value that is not read by any subsequent instruction. Calculating or retrieving a value only to then overwrite it or throw it away, could indicate a serious error in the code. Even if it's not an error, it is at best a waste of resources. Therefore all calculated values should be used.
Noncompliant Code Example
i = a + b; // Noncompliant; calculation result not used before value is overwritten i = compute();
Compliant Solution
i = a + b; i += compute();
Exceptions
This rule ignores initializations to -1, 0, 1, null
, true
, false
and ""
.
See
- MITRE, CWE-563 - Assignment to Variable without Use ('Unused Variable')
- CERT, MSC13-C. - Detect and remove unused values
- CERT, MSC56-J. - Detect and remove superfluous code and values
Refactor this method to reduce its Cognitive Complexity from 29 to the 15 allowed. Open
public static List<CIEventCause> processCauses(Run<?, ?> run) {
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Cognitive Complexity is a measure of how hard the control flow of a method is to understand. Methods with high Cognitive Complexity will be difficult to maintain.