org.molgenis.data.postgresql.PostgreSqlIdGenerator Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of molgenis-data-postgresql Show documentation

Data layer persistence in PostgreSQL.

There is a newer version: 8.4.5

Show newest version

package org.molgenis.data.postgresql;

import java.util.regex.Pattern;
import org.molgenis.data.meta.AbstractMetadataIdGenerator;
import org.molgenis.data.meta.model.Attribute;
import org.molgenis.data.meta.model.EntityType;

/** Generator for PostgreSQL table, column, key, trigger etc. identifiers. */
public class PostgreSqlIdGenerator extends AbstractMetadataIdGenerator {
  private static final Pattern PATTERN_WORD = Pattern.compile("\\w*");
  private static final Pattern PATTERN_WORD_REPLACE = Pattern.compile("\\W");

  /** Separator between identifier and name part in generated identifiers to improve readability. */
  private static final char SEPARATOR = '#';

  private final int maxIdentifierByteLength;

  PostgreSqlIdGenerator(int maxIdentifierByteLength) {
    if (maxIdentifierByteLength < 10) {
      throw new IllegalArgumentException("Max identifier byte length must be >= 10");
    }
    this.maxIdentifierByteLength = maxIdentifierByteLength;
  }

  @Override
  public String generateId(EntityType entityType) {
    String idHash = generateHashcode(entityType.getId());
    String truncatedId = truncateName(cleanName(entityType.getId()));
    return truncatedId + SEPARATOR + idHash;
  }

  @Override
  public String generateId(Attribute attribute) {
    String attrName = attribute.getName();
    if (PATTERN_WORD.matcher(attrName).matches() && attrName.length() <= maxIdentifierByteLength) {
      return attrName;
    } else {
      String idPart = generateHashcode(attribute.getIdentifier());
      String namePart = truncateName(cleanName(attribute.getName()));
      return namePart + SEPARATOR + idPart;
    }
  }

  private String cleanName(String name) {
    return PATTERN_WORD_REPLACE.matcher(name).replaceAll("");
  }

  private String truncateName(String name) {
    int maxNameLength = maxIdentifierByteLength - 8 - 1; // -8 for identifier part, -1 for separator
    return name.length() < maxNameLength ? name : name.substring(0, maxNameLength);
  }
}