prasadtalasila/BITS-Darshini

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.

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.

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.

Checks that the groups of import declarations appear in the order specifiedby the user. If there is an import but its group is not specified in theconfiguration such an import should be placed at the end of the import list.

This documentation is written and maintained by the Checkstyle community and is covered under the same license as the Checkstyle project.

Checks that the groups of import declarations appear in the order specifiedby the user. If there is an import but its group is not specified in theconfiguration such an import should be placed at the end of the import list.

This documentation is written and maintained by the Checkstyle community and is covered under the same license as the Checkstyle project.

Checks thatJavadoc summary sentence does not contain phrases that are not recommended to use.Summaries that contain only the {@inheritDoc} tag are skipped. Check alsoviolate Javadoc that does not contain first sentence.

This documentation is written and maintained by the Checkstyle community and is covered under the same license as the Checkstyle project.

Checks that the groups of import declarations appear in the order specifiedby the user. If there is an import but its group is not specified in theconfiguration such an import should be placed at the end of the import list.

This documentation is written and maintained by the Checkstyle community and is covered under the same license as the Checkstyle project.

Checks that the groups of import declarations appear in the order specifiedby the user. If there is an import but its group is not specified in theconfiguration such an import should be placed at the end of the import list.

This documentation is written and maintained by the Checkstyle community and is covered under the same license as the Checkstyle project.

Checks that the groups of import declarations appear in the order specifiedby the user. If there is an import but its group is not specified in theconfiguration such an import should be placed at the end of the import list.

This documentation is written and maintained by the Checkstyle community and is covered under the same license as the Checkstyle project.

Checks for empty line separators before package, all import declarations,fields, constructors, methods, nested classes,static initializers and instance initializers.

Checks for empty line separators before not only statements butimplementation and documentation comments and blocks as well.

ATTENTION: empty line separator is required between token siblings,not after line where token is found.If token does not have same type sibling then empty lineis required at its end (for example for CLASS_DEF it is after '}').Also, trailing comments are skipped.

ATTENTION: violations from multiple empty lines cannot be suppressed via XPath:#8179.

This documentation is written and maintained by the Checkstyle community and is covered under the same license as the Checkstyle project.

Checks that the groups of import declarations appear in the order specifiedby the user. If there is an import but its group is not specified in theconfiguration such an import should be placed at the end of the import list.

This documentation is written and maintained by the Checkstyle community and is covered under the same license as the Checkstyle project.

Checks that the groups of import declarations appear in the order specifiedby the user. If there is an import but its group is not specified in theconfiguration such an import should be placed at the end of the import list.

This documentation is written and maintained by the Checkstyle community and is covered under the same license as the Checkstyle project.

Checks that the groups of import declarations appear in the order specifiedby the user. If there is an import but its group is not specified in theconfiguration such an import should be placed at the end of the import list.

This documentation is written and maintained by the Checkstyle community and is covered under the same license as the Checkstyle project.

UnnecessaryLocalBeforeReturn

Since: PMD 3.3

Priority: Medium

Categories: Style

Remediation Points: 50000

Avoid the creation of unnecessary local variables

Example:

public class Foo {
 public int foo() {
 int x = doSomething();
 return x; // instead, just 'return doSomething();'
 }
}

ConfusingTernary

Since: PMD 1.9

Priority: Medium

Categories: Style

Remediation Points: 50000

Avoid negation within an 'if' expression with an 'else' clause. For example, rephrase: if (x != y) diff(); else same(); as: if (x == y) same(); else diff();. Most 'if (x != y)' cases without an 'else' are often return cases, so consistent use of this rule makes the code easier to read. Also, this resolves trivial ordering problems, such as 'does the error case go first?' or 'does the common case go first?'.

Example:

boolean bar(int x, int y) {
 return (x != y) ? diff : same;
}

ConfusingTernary

Since: PMD 1.9

Priority: Medium

Categories: Style

Remediation Points: 50000

Avoid negation within an 'if' expression with an 'else' clause. For example, rephrase: if (x != y) diff(); else same(); as: if (x == y) same(); else diff();. Most 'if (x != y)' cases without an 'else' are often return cases, so consistent use of this rule makes the code easier to read. Also, this resolves trivial ordering problems, such as 'does the error case go first?' or 'does the common case go first?'.

Example:

boolean bar(int x, int y) {
 return (x != y) ? diff : same;
}