Method onCommand
has a Cognitive Complexity of 22 (exceeds 5 allowed). Consider refactoring. Open
public boolean onCommand(CommandSender commandSender, Command command, String s, String[] args) {
if (!(commandSender instanceof Player)) {
commandSender.sendMessage(main.prefix + "Only players can use this command!");
return true;
}
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Cognitive Complexity
Cognitive Complexity is a measure of how difficult a unit of code is to intuitively understand. Unlike Cyclomatic Complexity, which determines how difficult your code will be to test, Cognitive Complexity tells you how difficult your code will be to read and comprehend.
A method's cognitive complexity is based on a few simple rules:
- Code is not considered more complex when it uses shorthand that the language provides for collapsing multiple statements into one
- Code is considered more complex for each "break in the linear flow of the code"
- Code is considered more complex when "flow breaking structures are nested"
Further reading
Method onCommand
has 64 lines of code (exceeds 25 allowed). Consider refactoring. Open
public boolean onCommand(CommandSender commandSender, Command command, String s, String[] args) {
if (!(commandSender instanceof Player)) {
commandSender.sendMessage(main.prefix + "Only players can use this command!");
return true;
}
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Avoid too many return
statements within this method. Open
return true;
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Avoid too many return
statements within this method. Open
return true;
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Avoid too many return
statements within this method. Open
return true;
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Avoid too many return
statements within this method. Open
return true;
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Avoid too many return
statements within this method. Open
return true;
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Avoid too many return
statements within this method. Open
return true;
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Avoid too many return
statements within this method. Open
return true;
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Avoid too many return
statements within this method. Open
return true;
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Avoid too many return
statements within this method. Open
return true;
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Avoid too many return
statements within this method. Open
return true;
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Avoid too many return
statements within this method. Open
return true;
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Avoid too many return
statements within this method. Open
return true;
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Refactor this method to reduce its Cognitive Complexity from 22 to the 15 allowed. Open
public boolean onCommand(CommandSender commandSender, Command command, String s, String[] args) {
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- Exclude checks
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
Remove these unused method parameters. Open
public boolean onCommand(CommandSender commandSender, Command command, String s, String[] args) {
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- Exclude checks
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
Define a constant instead of duplicating this literal "Please provide an arena name(ID)" 4 times. Open
player.sendMessage("Please provide an arena name(ID)");
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- Exclude checks
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.
Refactor this method to not always return the same value. Open
public boolean onCommand(CommandSender commandSender, Command command, String s, String[] args) {
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- Exclude checks
When a method is designed to return an invariant value, it may be poor design, but it shouldn't adversely affect the outcome of your program. However, when it happens on all paths through the logic, it is surely a bug.
This rule raises an issue when a method contains several return
statements that all return the same value.
Noncompliant Code Example
int foo(int a) { int b = 12; if (a == 1) { return b; } return b; // Noncompliant }
Similar blocks of code found in 2 locations. Consider refactoring. Open
if (args[0].equalsIgnoreCase("create")) {
if (args.length == 1) {
player.sendMessage("Please provide an arena name(ID)");
return true;
}
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Duplicated Code
Duplicated code can lead to software that is hard to understand and difficult to change. The Don't Repeat Yourself (DRY) principle states:
Every piece of knowledge must have a single, unambiguous, authoritative representation within a system.
When you violate DRY, bugs and maintenance problems are sure to follow. Duplicated code has a tendency to both continue to replicate and also to diverge (leaving bugs as two similar implementations differ in subtle ways).
Tuning
This issue has a mass of 90.
We set useful threshold defaults for the languages we support but you may want to adjust these settings based on your project guidelines.
The threshold configuration represents the minimum mass a code block must have to be analyzed for duplication. The lower the threshold, the more fine-grained the comparison.
If the engine is too easily reporting duplication, try raising the threshold. If you suspect that the engine isn't catching enough duplication, try lowering the threshold. The best setting tends to differ from language to language.
See codeclimate-duplication
's documentation for more information about tuning the mass threshold in your .codeclimate.yml
.
Refactorings
- Extract Method
- Extract Class
- Form Template Method
- Introduce Null Object
- Pull Up Method
- Pull Up Field
- Substitute Algorithm
Further Reading
- Don't Repeat Yourself on the C2 Wiki
- Duplicated Code on SourceMaking
- Refactoring: Improving the Design of Existing Code by Martin Fowler. Duplicated Code, p76
Similar blocks of code found in 2 locations. Consider refactoring. Open
if (args[0].equalsIgnoreCase("delete")) {
if (args.length == 1) {
player.sendMessage("Please provide an arena name(ID)");
return true;
}
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Duplicated Code
Duplicated code can lead to software that is hard to understand and difficult to change. The Don't Repeat Yourself (DRY) principle states:
Every piece of knowledge must have a single, unambiguous, authoritative representation within a system.
When you violate DRY, bugs and maintenance problems are sure to follow. Duplicated code has a tendency to both continue to replicate and also to diverge (leaving bugs as two similar implementations differ in subtle ways).
Tuning
This issue has a mass of 90.
We set useful threshold defaults for the languages we support but you may want to adjust these settings based on your project guidelines.
The threshold configuration represents the minimum mass a code block must have to be analyzed for duplication. The lower the threshold, the more fine-grained the comparison.
If the engine is too easily reporting duplication, try raising the threshold. If you suspect that the engine isn't catching enough duplication, try lowering the threshold. The best setting tends to differ from language to language.
See codeclimate-duplication
's documentation for more information about tuning the mass threshold in your .codeclimate.yml
.
Refactorings
- Extract Method
- Extract Class
- Form Template Method
- Introduce Null Object
- Pull Up Method
- Pull Up Field
- Substitute Algorithm
Further Reading
- Don't Repeat Yourself on the C2 Wiki
- Duplicated Code on SourceMaking
- Refactoring: Improving the Design of Existing Code by Martin Fowler. Duplicated Code, p76