Add a private constructor to hide the implicit public one. Open
public final class UdpHeader {
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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.
Rename this constant name to match the regular expression '^[A-Z][A-Z0-9]*(_[A-Z0-9]+)*$'. Open
public static final int LENGTH__START_BYTE = 4;
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Shared coding conventions allow teams to collaborate efficiently. This rule checks that all constant names match a provided regular expression.
Noncompliant Code Example
With the default regular expression ^[A-Z][A-Z0-9]*(_[A-Z0-9]+)*$
:
public class MyClass { public static final int first = 1; } public enum MyEnum { first; }
Compliant Solution
public class MyClass { public static final int FIRST = 1; } public enum MyEnum { FIRST; }
Rename this constant name to match the regular expression '^[A-Z][A-Z0-9]*(_[A-Z0-9]+)*$'. Open
public static final int LENGTH__END_BIT = 47;
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Shared coding conventions allow teams to collaborate efficiently. This rule checks that all constant names match a provided regular expression.
Noncompliant Code Example
With the default regular expression ^[A-Z][A-Z0-9]*(_[A-Z0-9]+)*$
:
public class MyClass { public static final int first = 1; } public enum MyEnum { first; }
Compliant Solution
public class MyClass { public static final int FIRST = 1; } public enum MyEnum { FIRST; }
Rename this constant name to match the regular expression '^[A-Z][A-Z0-9]*(_[A-Z0-9]+)*$'. Open
public static final int LENGTH__START_BIT = 32;
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Shared coding conventions allow teams to collaborate efficiently. This rule checks that all constant names match a provided regular expression.
Noncompliant Code Example
With the default regular expression ^[A-Z][A-Z0-9]*(_[A-Z0-9]+)*$
:
public class MyClass { public static final int first = 1; } public enum MyEnum { first; }
Compliant Solution
public class MyClass { public static final int FIRST = 1; } public enum MyEnum { FIRST; }
Rename this constant name to match the regular expression '^[A-Z][A-Z0-9]*(_[A-Z0-9]+)*$'. Open
public static final int LENGTH__END_BYTE = 5;
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- Exclude checks
Shared coding conventions allow teams to collaborate efficiently. This rule checks that all constant names match a provided regular expression.
Noncompliant Code Example
With the default regular expression ^[A-Z][A-Z0-9]*(_[A-Z0-9]+)*$
:
public class MyClass { public static final int first = 1; } public enum MyEnum { first; }
Compliant Solution
public class MyClass { public static final int FIRST = 1; } public enum MyEnum { FIRST; }