JavaParserTypeResolutionService.java

package org.springframework.roo.classpath.antlrjavaparser;

import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.IOException;

import org.apache.commons.io.FileUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.Validate;
import org.apache.felix.scr.annotations.Component;
import org.apache.felix.scr.annotations.Service;
import org.springframework.roo.classpath.TypeResolutionService;
import org.springframework.roo.model.JavaPackage;
import org.springframework.roo.model.JavaType;

import com.github.antlrjavaparser.JavaParser;
import com.github.antlrjavaparser.ParseException;
import com.github.antlrjavaparser.api.CompilationUnit;
import com.github.antlrjavaparser.api.body.TypeDeclaration;

@Component
@Service
public class JavaParserTypeResolutionService implements TypeResolutionService {

  @Override
  public final JavaType getJavaType(final String fileIdentifier) {
    Validate.notBlank(fileIdentifier, "Compilation unit path required");
    Validate.isTrue(new File(fileIdentifier).exists(), "The file doesn't exist");
    Validate.isTrue(new File(fileIdentifier).isFile(), "The identifier doesn't represent a file");
    try {
      final File file = new File(fileIdentifier);
      String typeContents = "";
      try {
        typeContents = FileUtils.readFileToString(file);
      } catch (final IOException ignored) {
      }
      if (StringUtils.isBlank(typeContents)) {
        return null;
      }
      final CompilationUnit compilationUnit =
          JavaParser.parse(new ByteArrayInputStream(typeContents.getBytes()));
      final String typeName =
          fileIdentifier.substring(fileIdentifier.lastIndexOf(File.separator) + 1,
              fileIdentifier.lastIndexOf("."));
      for (final TypeDeclaration typeDeclaration : compilationUnit.getTypes()) {
        if (typeName.equals(typeDeclaration.getName())) {
          return new JavaType(compilationUnit.getPackage().getName().getName() + "."
              + typeDeclaration.getName());
        }
      }
      return null;
    } catch (final IOException e) {
      throw new IllegalStateException(e);
    } catch (final ParseException e) {
      throw new IllegalStateException("Failed to parse " + fileIdentifier + " : " + e.getMessage());
    }
  }

  @Override
  public final JavaPackage getPackage(final String fileIdentifier) {
    Validate.notBlank(fileIdentifier, "Compilation unit path required");
    Validate.isTrue(new File(fileIdentifier).exists(), "The file doesn't exist");
    Validate.isTrue(new File(fileIdentifier).isFile(), "The identifier doesn't represent a file");
    try {
      final File file = new File(fileIdentifier);
      String typeContents = "";
      try {
        typeContents = FileUtils.readFileToString(file);
      } catch (final IOException ignored) {
      }
      if (StringUtils.isBlank(typeContents)) {
        return null;
      }
      final CompilationUnit compilationUnit =
          JavaParser.parse(new ByteArrayInputStream(typeContents.getBytes()));
      if (compilationUnit == null || compilationUnit.getPackage() == null) {
        return null;
      }
      return new JavaPackage(compilationUnit.getPackage().getName().toString());
    } catch (final IOException e) {
      throw new IllegalStateException(e);
    } catch (final ParseException e) {
      throw new IllegalStateException("Failed to parse " + fileIdentifier + " : " + e.getMessage());
    }
  }
}