Remove use of @PostContruct

builder/src/main/java/net/kemitix/checkstyle/ruleset/builder/BuilderConfiguration.java

@@ -26,6 +26,12 @@ import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 
 import java.io.IOException;
+import java.util.AbstractMap;
+import java.util.List;
+import java.util.Map;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
 /**
  * Configuration for Builder.
@@ -46,4 +52,35 @@ public class BuilderConfiguration {
     public ClassPath classPath() throws IOException {
         return ClassPath.from(getClass().getClassLoader());
     }
+
+    /**
+     * A Map of rules for each RuleSource.
+     *
+     * @param packageScanner the PackageScanner
+     *
+     * @return a Map with a list of check classes for each rule source
+     */
+    @Bean
+    public Map<RuleSource, List<String>> checkClasses(final PackageScanner packageScanner) {
+        return Stream.of(RuleSource.values())
+                .map(toRuleSourceEntry(packageScanner))
+                .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
+    }
+
+    private static Function<RuleSource, AbstractMap.SimpleEntry<RuleSource, List<String>>> toRuleSourceEntry(
+            final PackageScanner packageScanner
+                                                                                                            ) {
+        return source -> new AbstractMap.SimpleEntry<>(
+                source,
+                classesInSource(source, packageScanner)
+        );
+    }
+
+    private static List<String> classesInSource(
+            final RuleSource source,
+            final PackageScanner packageScanner
+                                               ) {
+        return packageScanner.apply(source)
+                .collect(Collectors.toList());
+    }
 }

builder/src/main/java/net/kemitix/checkstyle/ruleset/builder/DefaultRuleClassLocator.java

@@ -24,13 +24,9 @@ package net.kemitix.checkstyle.ruleset.builder;
 import lombok.RequiredArgsConstructor;
 import org.springframework.stereotype.Service;
 
-import javax.annotation.PostConstruct;
-import java.util.AbstractMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
-import java.util.stream.Collectors;
-import java.util.stream.Stream;
 
 /**
  * Default implementation of {@link RuleClassLocator}.
@@ -41,38 +37,30 @@ import java.util.stream.Stream;
 @RequiredArgsConstructor
 public class DefaultRuleClassLocator implements RuleClassLocator {
 
-    private final PackageScanner packageScanner;
-
-    private Map<RuleSource, List<String>> checkClasses;
-
-    /**
-     * Initialise class lists for {@link RuleSource}s.
-     */
-    @PostConstruct
-    public final void init() {
-        checkClasses = Stream.of(RuleSource.values())
-                             .map(source -> new AbstractMap.SimpleEntry<>(
-                                     source, packageScanner.apply(source)
-                                                           .collect(Collectors.toList())))
-                             .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
-    }
+    private final Map<RuleSource, List<String>> checkClasses;
 
     @Override
     public final String apply(final Rule rule) {
         return getCanonicalClassName(rule.getSource(), rule.getName());
     }
 
-    private String getCanonicalClassName(final RuleSource source, final String name) {
+    private String getCanonicalClassName(
+            final RuleSource source,
+            final String name
+                                        ) {
         Objects.requireNonNull(checkClasses, "init() method not called");
         return checkClasses.get(source)
-                           .stream()
-                           .sorted()
-                           .filter(classname -> byRuleName(classname, name))
-                           .findFirst()
-                           .orElseThrow(() -> new CheckstyleClassNotFoundException(name));
+                .stream()
+                .sorted()
+                .filter(classname -> byRuleName(classname, name))
+                .findFirst()
+                .orElseThrow(() -> new CheckstyleClassNotFoundException(name));
     }
 
-    private boolean byRuleName(final String classname, final String name) {
+    private boolean byRuleName(
+            final String classname,
+            final String name
+                              ) {
         final String classNameWithDelimiter = "." + name;
         return classname.endsWith(classNameWithDelimiter) || classname.endsWith(classNameWithDelimiter + "Check");
     }

builder/src/test/java/net/kemitix/checkstyle/ruleset/builder/DefaultRuleClassLocatorTest.java

@@ -4,7 +4,9 @@ import org.junit.Before;
 import org.junit.Test;
 
 import java.util.Collections;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatNullPointerException;
@@ -19,14 +21,9 @@ import static org.mockito.Mockito.mock;
  */
 public class DefaultRuleClassLocatorTest {
 
-    private DefaultRuleClassLocator subject;
+    private final Map<RuleSource, List<String>> checkClasses = new HashMap<>();
 
-    private PackageScanner packageScanner = mock(PackageScanner.class);
-
-    @Before
-    public void setUp() {
-        subject = new DefaultRuleClassLocator(packageScanner);
-    }
+    private final DefaultRuleClassLocator subject = new DefaultRuleClassLocator(checkClasses);
 
     @Test
     public void canLookupRuleWithClassNameEndingInCheck() {
@@ -35,9 +32,8 @@ public class DefaultRuleClassLocatorTest {
         final String expected = "com.puppycrawl.tools.checkstyle.checks.regexp.RegexpOnFilenameCheck";
         final List<String> checkstyleClasses = Collections.singletonList(expected);
         final List<String> sevntuClasses = Collections.emptyList();
-        given(packageScanner.apply(RuleSource.CHECKSTYLE)).willReturn(checkstyleClasses.stream());
-        given(packageScanner.apply(RuleSource.SEVNTU)).willReturn(sevntuClasses.stream());
-        subject.init();
+        checkClasses.put(RuleSource.CHECKSTYLE, checkstyleClasses);
+        checkClasses.put(RuleSource.SEVNTU, sevntuClasses);
         final Rule rule = createCheckstyleRule(rulename);
         //when
         final String result = subject.apply(rule);
@@ -52,9 +48,8 @@ public class DefaultRuleClassLocatorTest {
         final String expected = "com.puppycrawl.tools.checkstyle.checks.regexp.RegexpOnFilename";
         final List<String> checkstyleClasses = Collections.singletonList(expected);
         final List<String> sevntuClasses = Collections.emptyList();
-        given(packageScanner.apply(RuleSource.CHECKSTYLE)).willReturn(checkstyleClasses.stream());
-        given(packageScanner.apply(RuleSource.SEVNTU)).willReturn(sevntuClasses.stream());
-        subject.init();
+        checkClasses.put(RuleSource.CHECKSTYLE, checkstyleClasses);
+        checkClasses.put(RuleSource.SEVNTU, sevntuClasses);
         final Rule rule = createCheckstyleRule(rulename);
         //when
         final String result = subject.apply(rule);
@@ -69,9 +64,8 @@ public class DefaultRuleClassLocatorTest {
         final String expected = "com.puppycrawl.tools.checkstyle.checks.regexp.RegexpOnFilenameNoMatch";
         final List<String> checkstyleClasses = Collections.singletonList(expected);
         final List<String> sevntuClasses = Collections.emptyList();
-        given(packageScanner.apply(RuleSource.CHECKSTYLE)).willReturn(checkstyleClasses.stream());
-        given(packageScanner.apply(RuleSource.SEVNTU)).willReturn(sevntuClasses.stream());
-        subject.init();
+        checkClasses.put(RuleSource.CHECKSTYLE, checkstyleClasses);
+        checkClasses.put(RuleSource.SEVNTU, sevntuClasses);
         final Rule rule = createCheckstyleRule(rulename);
         //then
         assertThatThrownBy(() -> subject.apply(rule))
@@ -79,13 +73,6 @@ public class DefaultRuleClassLocatorTest {
                 .hasMessage("No class found to implement RegexpOnFilename");
     }
 
-    @Test
-    public void throwsNullPointerExceptionWhenInitNotCalled() {
-        assertThatNullPointerException()
-                .isThrownBy(() -> subject.apply(new Rule()))
-                .withMessage("init() method not called");
-    }
-
     private Rule createCheckstyleRule(final String rulename) {
         final Rule rule = new Rule();
         rule.setSource(RuleSource.CHECKSTYLE);