ebean/src/main/java/com/avaje/ebeaninternal/server/expression/NullExpression.java

package com.avaje.ebeaninternal.server.expression;

import com.avaje.ebean.event.BeanQueryRequest;
import com.avaje.ebeaninternal.api.HashQueryPlanBuilder;
import com.avaje.ebeaninternal.api.SpiExpressionRequest;
import com.avaje.ebeaninternal.server.el.ElPropertyValue;


/**
 * Slightly redundant as Query.setId() ultimately also does the same job.
 */
class NullExpression extends AbstractExpression {

  private static final long serialVersionUID = 4246991057451128269L;

  private final boolean notNull;

  NullExpression(String propertyName, boolean notNull) {
    super(propertyName);
    this.notNull = notNull;
  }

  public void addBindValues(SpiExpressionRequest request) {

  }

  public void addSql(SpiExpressionRequest request) {

    String propertyName = getPropertyName();

    String nullExpr = notNull ? " is not null " : " is null ";

    ElPropertyValue prop = getElProp(request);
    if (prop != null && prop.isAssocId()) {
      request.append(prop.getAssocOneIdExpr(propertyName, nullExpr));
      return;
    }

    request.append(propertyName).append(nullExpr);
  }

  /**
   * Based on notNull flag and the propertyName.
   */
  public void queryAutoFetchHash(HashQueryPlanBuilder builder) {
    builder.add(NullExpression.class).add(notNull).add(propName);
  }

  public void queryPlanHash(BeanQueryRequest<?> request, HashQueryPlanBuilder builder) {
    queryAutoFetchHash(builder);
  }

  public int queryBindHash() {
    return (notNull ? 1 : 0);
  }
}