Contains rules about migrating from one JDK version to another. Don’t use these rules directly, rather, use a wrapper ruleset such as migrating_to_13.xml.
Since: PMD 3.4
Priority: 3
Consider replacing Vector usages with the newer java.util.ArrayList if expensive thread-safe operations are not required.
//Type/ReferenceType/ClassOrInterfaceType[@Image='Vector']
Example(s):
public class Foo {
void bar() {
Vector v = new Vector();
}
}
Since: PMD 3.4
Priority: 3
Consider replacing Hashtable usage with the newer java.util.Map if thread safety is not required.
//Type/ReferenceType/ClassOrInterfaceType[@Image='Hashtable']
Example(s):
public class Foo {
void bar() {
Hashtable h = new Hashtable();
}
}
Since: PMD 3.4
Priority: 3
Consider replacing Enumeration usages with the newer java.util.Iterator
//ImplementsList/ClassOrInterfaceType[@Image='Enumeration']
Example(s):
public class Foo implements Enumeration {
private int x = 42;
public boolean hasMoreElements() {
return true;
}
public Object nextElement() {
return String.valueOf(i++);
}
}
Since: PMD 3.4
Priority: 2
Use of the term ‘enum’ will conflict with newer versions of Java since it is a reserved word.
//VariableDeclaratorId[@Image='enum']
Example(s):
public class A {
public class foo {
String enum = "foo";
}
}
Since: PMD 3.4
Priority: 2
Use of the term ‘assert’ will conflict with newer versions of Java since it is a reserved word.
//VariableDeclaratorId[@Image='assert']
Example(s):
public class A {
public class foo {
String assert = "foo";
}
}
Since: PMD 3.5
Priority: 2
Calling new Integer() causes memory allocation that can be avoided by the static Integer.valueOf(). It makes use of an internal cache that recycles earlier instances making it more memory efficient.
//PrimaryPrefix
/AllocationExpression
[not (ArrayDimsAndInits)
and (ClassOrInterfaceType/@Image='Integer'
or ClassOrInterfaceType/@Image='java.lang.Integer')]
Example(s):
public class Foo {
private Integer i = new Integer(0); // change to Integer i = Integer.valueOf(0);
}
Since: PMD 4.0
Priority: 2
Calling new Byte() causes memory allocation that can be avoided by the static Byte.valueOf(). It makes use of an internal cache that recycles earlier instances making it more memory efficient.
//PrimaryPrefix/AllocationExpression
[not (ArrayDimsAndInits)
and (ClassOrInterfaceType/@Image='Byte'
or ClassOrInterfaceType/@Image='java.lang.Byte')]
Example(s):
public class Foo {
private Byte i = new Byte(0); // change to Byte i = Byte.valueOf(0);
}
Since: PMD 4.0
Priority: 2
Calling new Short() causes memory allocation that can be avoided by the static Short.valueOf(). It makes use of an internal cache that recycles earlier instances making it more memory efficient.
//PrimaryPrefix
/AllocationExpression
[not (ArrayDimsAndInits)
and (ClassOrInterfaceType/@Image='Short'
or ClassOrInterfaceType/@Image='java.lang.Short')]
Example(s):
public class Foo {
private Short i = new Short(0); // change to Short i = Short.valueOf(0);
}
Since: PMD 4.0
Priority: 2
Calling new Long() causes memory allocation that can be avoided by the static Long.valueOf(). It makes use of an internal cache that recycles earlier instances making it more memory efficient.
//PrimaryPrefix
/AllocationExpression
[not (ArrayDimsAndInits)
and (ClassOrInterfaceType/@Image='Long'
or ClassOrInterfaceType/@Image='java.lang.Long')]
Example(s):
public class Foo {
private Long i = new Long(0); // change to Long i = Long.valueOf(0);
}
Since: PMD 4.0
Priority: 3
In JUnit 3, the setUp method was used to set up all data entities required in running tests. JUnit 4 skips the setUp method and executes all methods annotated with @Before before all tests
//ClassOrInterfaceBodyDeclaration[MethodDeclaration/MethodDeclarator[@Image='setUp']]
[count(Annotation/MarkerAnnotation/Name[@Image='Before'])=0]
Example(s):
public class MyTest {
public void setUp() {
bad();
}
}
public class MyTest2 {
@Before public void setUp() {
good();
}
}
Since: PMD 4.0
Priority: 3
In JUnit 3, the tearDown method was used to clean up all data entities required in running tests. JUnit 4 skips the tearDown method and executes all methods annotated with @After after running each test
//ClassOrInterfaceBodyDeclaration[MethodDeclaration/MethodDeclarator[@Image='tearDown']]
[count(Annotation/MarkerAnnotation/Name[@Image='After'])=0]
Example(s):
public class MyTest {
public void tearDown() {
bad();
}
}
public class MyTest2 {
@After public void tearDown() {
good();
}
}
Since: PMD 4.0
Priority: 3
In JUnit 3, the framework executed all methods which started with the word test as a unit test. In JUnit 4, only methods annotated with the @Test annotation are executed.
//ClassOrInterfaceBodyDeclaration[MethodDeclaration[@Public='true']/MethodDeclarator[starts-with(@Image,'test')]]
[count(Annotation//Name[@Image='Test'])=0]
Example(s):
public class MyTest {
public void testBad() {
doSomething();
}
@Test
public void testGood() {
doSomething();
}
}
Since: PMD 4.0
Priority: 3
In JUnit 3, test suites are indicated by the suite() method. In JUnit 4, suites are indicated through the @RunWith(Suite.class) annotation.
//ClassOrInterfaceBodyDeclaration[MethodDeclaration/MethodDeclarator[@Image='suite']]
[MethodDeclaration/ResultType/Type/ReferenceType/ClassOrInterfaceType[@Image='Test' or @Image = 'junit.framework.Test']]
[not(MethodDeclaration/Block//ClassOrInterfaceType[@Image='JUnit4TestAdapter'])]
Example(s):
public class BadExample extends TestCase{
public static Test suite(){
return new Suite();
}
}
@RunWith(Suite.class)
@SuiteClasses( { TestOne.class, TestTwo.class })
public class GoodTest {
}
Since: PMD 4.0
Priority: 3
In JUnit4, use the @Test(expected) annotation to denote tests that should throw exceptions.
This rule is defined by the following Java class: net.sourceforge.pmd.lang.java.rule.migrating.JUnitUseExpectedRule
Example(s):
public class MyTest {
@Test
public void testBad() {
try {
doSomething();
fail("should have thrown an exception");
} catch (Exception e) {
}
}
@Test(expected=Exception.class)
public void testGood() {
doSomething();
}
}
This rule has the following properties:
| Name | Default Value | Description |
|---|---|---|
| violationSuppressRegex | Suppress violations with messages matching a regular expression | |
| violationSuppressXPath | Suppress violations on nodes which match a given relative XPath expression. |