build-plugin/src/main/java/org/adrianwalker/multilinestring/EcjMultilineProcessor.java

// Code from https://github.com/benelog/multiline.git
// Based on Adrian Walker's blog post: http://www.adrianwalker.org/2011/12/java-multiline-string.html

package org.adrianwalker.multilinestring;

import java.util.Set;

import javax.annotation.processing.AbstractProcessor;
import javax.annotation.processing.ProcessingEnvironment;
import javax.annotation.processing.RoundEnvironment;
import javax.annotation.processing.SupportedAnnotationTypes;
import javax.annotation.processing.SupportedSourceVersion;
import javax.lang.model.SourceVersion;
import javax.lang.model.element.Element;
import javax.lang.model.element.TypeElement;
import javax.lang.model.util.Elements;

import org.eclipse.jdt.internal.compiler.apt.model.VariableElementImpl;
import org.eclipse.jdt.internal.compiler.ast.FieldDeclaration;
import org.eclipse.jdt.internal.compiler.ast.StringLiteral;
import org.eclipse.jdt.internal.compiler.lookup.FieldBinding;

import java.lang.reflect.Constructor;

@SupportedAnnotationTypes({"org.adrianwalker.multilinestring.Multiline"})
@SupportedSourceVersion(SourceVersion.RELEASE_8)
public final class EcjMultilineProcessor extends AbstractProcessor {

  private Elements elementUtils;

  @Override
  public void init(final ProcessingEnvironment procEnv) {
    super.init(procEnv);
    this.elementUtils = procEnv.getElementUtils();
  }

  @Override
  public boolean process(final Set<? extends TypeElement> annotations, final RoundEnvironment roundEnv) {
    Set<? extends Element> fields = roundEnv.getElementsAnnotatedWith(Multiline.class);

    for (Element field : fields) {
      String docComment = elementUtils.getDocComment(field);

      if (null != docComment) {
        VariableElementImpl fieldElem = (VariableElementImpl) field;
        FieldBinding biding = (FieldBinding) fieldElem._binding;
        FieldDeclaration decl = biding.sourceField();
        StringLiteral string = new StringLiteral(docComment.toCharArray(), decl.sourceStart, decl.sourceEnd, decl.sourceStart);
        decl.initialization = string;
      }
    }
    return true;
  }
}