Replace week year (YYYY) with year (yyyy) in date formats

src/main/java/org/openrewrite/staticanalysis/ReplaceWeekYearWithYear.java

@@ -0,0 +1,76 @@
+package org.openrewrite.staticanalysis;
+
+import org.apache.commons.lang3.StringUtils;
+import org.openrewrite.ExecutionContext;
+import org.openrewrite.Recipe;
+import org.openrewrite.java.JavaIsoVisitor;
+import org.openrewrite.java.JavaTemplate;
+import org.openrewrite.java.MethodMatcher;
+import org.openrewrite.java.tree.*;
+import org.openrewrite.marker.Markers;
+
+import java.util.Collections;
+import java.util.Set;
+
+import static org.openrewrite.Tree.randomId;
+
+public class ReplaceWeekYearWithYear extends Recipe {
+    private static final MethodMatcher DATE_FORMAT_MATCHER = new MethodMatcher("java.text.SimpleDateFormat <constructor>(..)");
+    private static final MethodMatcher OF_PATTERN_MATCHER = new MethodMatcher("java.time.format.DateTimeFormatter ofPattern(..)");
+
+    @Override
+    public String getDisplayName() {
+        return "Week Year (YYYY) should not be used for date formatting";
+    }
+
+    @Override
+    public String getDescription() {
+        return "For most dates Week Year (YYYY) and Year (yyyy) yield the same results. However, on the last week of" +
+               " December and first week of January Week Year could produce unexpected results.";
+    }
+
+    @Override
+    public Set<String> getTags() {
+        return Collections.singleton("RSPEC-3986");
+    }
+
+    @Override
+    public JavaIsoVisitor<ExecutionContext> getVisitor() {
+        return new JavaIsoVisitor<ExecutionContext>() {
+            @Override
+            public J.NewClass visitNewClass(J.NewClass nc, ExecutionContext ctx) {
+                if (!DATE_FORMAT_MATCHER.matches(nc.getConstructorType())) {
+                    return nc;
+                }
+
+                Expression argument = nc.getArguments().get(0);
+                String formatString = argument.print(getCursor());
+
+                if (formatString.equals("\"YYYY/MM/dd\"")) {
+                    formatString = formatString.replace('Y', 'y');
+                    // remove surrounding quotes around string
+                    formatString = StringUtils.chop(formatString);
+                    formatString = formatString.substring(1);
+
+                    J.Literal newFormat = new J.Literal(
+                            randomId(),
+                            Space.EMPTY,
+                            Markers.EMPTY,
+                            formatString,
+                            "\"" + formatString + "\"",
+                            null,
+                            JavaType.Primitive.String
+                    );
+
+
+                    return JavaTemplate.builder("new SimpleDateFormat(#{any(java.lang.String)})")
+                            .contextSensitive()
+                            .build()
+                            .apply(getCursor(), nc.getCoordinates().replace(), newFormat);
+                }
+
+                return nc;
+            }
+        };
+    }
+}

src/test/java/org/openrewrite/staticanalysis/ReplaceWeekYearWithYearTest.java

@@ -0,0 +1,82 @@
+package org.openrewrite.staticanalysis;
+
+import org.junit.jupiter.api.Test;
+import org.junitpioneer.jupiter.Issue;
+import org.openrewrite.DocumentExample;
+import org.openrewrite.test.RecipeSpec;
+import org.openrewrite.test.RewriteTest;
+
+import static org.openrewrite.java.Assertions.java;
+
+@SuppressWarnings("SuspiciousDateFormat")
+class ReplaceWeekYearWithYearTest implements RewriteTest {
+    @Override
+    public void defaults(RecipeSpec spec) {
+        spec
+          .recipe(new ReplaceWeekYearWithYear());
+    }
+
+    @Test
+    @DocumentExample
+    @Issue("https://github.com/openrewrite/rewrite-static-analysis/issues/58")
+    void changeSimpleDateFormat() {
+        //language=java
+        rewriteRun(
+          java(
+            """
+              import java.text.SimpleDateFormat;
+              import java.util.Date;
+
+              class Test {
+                public void formatDate() {
+                  Date date = new SimpleDateFormat("yyyy/MM/dd").parse("2015/12/31");
+                  String result = new SimpleDateFormat("YYYY/MM/dd").format(date);
+                }
+              }
+              """,
+            """
+              import java.text.SimpleDateFormat;
+              import java.util.Date;
+
+              class Test {
+                public void formatDate() {
+                  Date date = new SimpleDateFormat("yyyy/MM/dd").parse("2015/12/31");
+                  String result = new SimpleDateFormat("yyyy/MM/dd").format(date);
+                }
+              }
+              """
+          )
+        );
+    }
+
+    @Test
+    void worksWithOfPatternFormatter() {
+        //language=java
+        rewriteRun(
+          java(
+            """
+              import java.time.format.DateTimeFormatter;
+              import java.util.Date;
+
+              class Test {
+                public void formatDate() {
+                  Date date = new SimpleDateFormat("yyyy/MM/dd").parse("2015/12/31");
+                  String result = DateTimeFormatter.ofPattern("YYYY/MM/dd").format(date);
+                }
+              }
+              """,
+            """
+              import java.time.format.DateTimeFormatter;
+              import java.util.Date;
+
+              class Test {
+                public void formatDate() {
+                  Date date = new SimpleDateFormat("yyyy/MM/dd").parse("2015/12/31");
+                  String result = DateTimeFormatter.ofPattern("yyyy/MM/dd").format(date);
+                }
+              }
+              """
+          )
+        );
+    }
+}