copied across the files from the maven sample

Author: MysterAitch

src/main/java/com/yourorganization/maven_sample/LogicPositivizer.java

@@ -0,0 +1,65 @@
+package com.yourorganization.maven_sample;
+
+import com.github.javaparser.ast.CompilationUnit;
+import com.github.javaparser.ast.expr.BinaryExpr;
+import com.github.javaparser.ast.stmt.IfStmt;
+import com.github.javaparser.ast.stmt.Statement;
+import com.github.javaparser.ast.visitor.ModifierVisitor;
+import com.github.javaparser.ast.visitor.Visitable;
+import com.github.javaparser.utils.CodeGenerationUtils;
+import com.github.javaparser.utils.Log;
+import com.github.javaparser.utils.SourceRoot;
+
+import java.nio.file.Paths;
+
+/**
+ * Some code that uses JavaParser.
+ */
+public class LogicPositivizer {
+    public static void main(String[] args) {
+        // JavaParser has a minimal logging class that normally logs nothing.
+        // Let's ask it to write to standard out:
+        Log.setAdapter(new Log.StandardOutStandardErrorAdapter());
+
+        // SourceRoot is a tool that read and writes Java files from packages on a certain root directory.
+        // In this case the root directory is found by taking the root from the current Maven module,
+        // with src/main/resources appended.
+        SourceRoot sourceRoot = new SourceRoot(CodeGenerationUtils.mavenModuleRoot(LogicPositivizer.class).resolve("src/main/resources"));
+
+        // Our sample is in the root of this directory, so no package name.
+        CompilationUnit cu = sourceRoot.parse("", "Blabla.java");
+
+        Log.info("Positivizing!");
+
+        cu.accept(new ModifierVisitor<Void>() {
+            /**
+             * For every if-statement, see if it has a comparison using "!=".
+             * Change it to "==" and switch the "then" and "else" statements around.
+             */
+            @Override
+            public Visitable visit(IfStmt n, Void arg) {
+                // Figure out what to get and what to cast simply by looking at the AST in a debugger!
+                n.getCondition().ifBinaryExpr(binaryExpr -> {
+                    if (binaryExpr.getOperator() == BinaryExpr.Operator.NOT_EQUALS && n.getElseStmt().isPresent()) {
+                        /* It's a good idea to clone nodes that you move around.
+                            JavaParser (or you) might get confused about who their parent is!
+                        */
+                        Statement thenStmt = n.getThenStmt().clone();
+                        Statement elseStmt = n.getElseStmt().get().clone();
+                        n.setThenStmt(elseStmt);
+                        n.setElseStmt(thenStmt);
+                        binaryExpr.setOperator(BinaryExpr.Operator.EQUALS);
+                    }
+                });
+                return super.visit(n, arg);
+            }
+        }, null);
+
+        // This saves all the files we just read to an output directory.
+        sourceRoot.saveAll(
+                // The path of the Maven module/project which contains the LogicPositivizer class.
+                CodeGenerationUtils.mavenModuleRoot(LogicPositivizer.class)
+                        // appended with a path to "output"
+                        .resolve(Paths.get("output")));
+    }
+}