Fix for #192 - Backslash literal in LIKE expression - Postgres (and H2, MySql) behaviour

src/main/java/com/avaje/ebean/config/dbplatform/DatabasePlatform.java

@@ -6,6 +6,7 @@ import javax.sql.DataSource;
 
 import com.avaje.ebean.BackgroundExecutor;
 import com.avaje.ebean.Query;
+
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -14,40 +15,61 @@ import org.slf4j.LoggerFactory;
  */
 public class DatabasePlatform {
 
-  /** The Constant logger. */
   private static final Logger logger = LoggerFactory.getLogger(DatabasePlatform.class);
 
-  /** The open quote used by quoted identifiers. */
+  /** 
+   * The open quote used by quoted identifiers. 
+   */
   protected String openQuote = "\"";
 
-  /** The close quote used by quoted identifiers. */
+  /**
+   *  The close quote used by quoted identifiers. 
+   */
   protected String closeQuote = "\"";
 
-  /** For limit/offset, row_number etc limiting of SQL queries. */
+  /** 
+   * For limit/offset, row_number etc limiting of SQL queries. 
+   */
   protected SqlLimiter sqlLimiter = new LimitOffsetSqlLimiter();
 
-  /** Mapping of JDBC to Database types. */
+  /** 
+   * Mapping of JDBC to Database types. 
+   */
   protected DbTypeMap dbTypeMap = new DbTypeMap();
 
-  /** DB specific DDL syntax. */
+  /** 
+   * DB specific DDL syntax. 
+   */
   protected DbDdlSyntax dbDdlSyntax = new DbDdlSyntax();
 
-  /** Defines DB identity/sequence features. */
+  /** 
+   * Defines DB identity/sequence features. 
+   */
   protected DbIdentity dbIdentity = new DbIdentity();
 
-  /** The JDBC type to map booleans to (by default). */
+  /** 
+   * The JDBC type to map booleans to (by default). 
+   */
   protected int booleanDbType = Types.BOOLEAN;
 
-  /** The JDBC type to map Blob to. */
+  /** 
+   * The JDBC type to map Blob to. 
+   */
   protected int blobDbType = Types.BLOB;
 
-  /** The JDBC type to map Clob to. */
+  /** 
+   * The JDBC type to map Clob to. 
+   */
   protected int clobDbType = Types.CLOB;
 
-  /** For Oracle treat empty strings as null. */
+  /** 
+   * For Oracle treat empty strings as null. 
+   */
   protected boolean treatEmptyStringsAsNull;
 
-  /** The name. */
+  /** 
+   * The database platform name. 
+   */
   protected String name = "generic";
 
   /**
@@ -57,6 +79,11 @@ public class DatabasePlatform {
    */
   private static final char BACK_TICK = '`';
 
+  /**
+   * The like clause. Can be overridden to disable default escape character.
+   */
+  protected String likeClause = "like ?";
+  
   protected DbEncrypt dbEncrypt;
 
   protected boolean idInExpandedForm;
@@ -299,4 +326,13 @@ public class DatabasePlatform {
 
     return sql;
   }
+
+  /**
+   * Returns the like clause used by this database platform.
+   * <p>
+   * This may include an escape clause to disable a default escape character.
+   */
+  public String getLikeClause() {
+    return likeClause;
+  }
 }

src/main/java/com/avaje/ebean/config/dbplatform/H2Platform.java

@@ -14,6 +14,7 @@ public class H2Platform extends DatabasePlatform {
     super();
     this.name = "h2";
     this.dbEncrypt = new H2DbEncrypt();
+    this.likeClause = "like ? escape''";
 
     // only support getGeneratedKeys with non-batch JDBC
     // so generally use SEQUENCE instead of IDENTITY for H2

src/main/java/com/avaje/ebean/config/dbplatform/MySqlPlatform.java

@@ -20,6 +20,7 @@ public class MySqlPlatform extends DatabasePlatform {
   public MySqlPlatform() {
     super();
     this.name = "mysql";
+    this.likeClause = "like ? escape''";
     this.selectCountWithAlias = true;
     this.dbEncrypt = new MySqlDbEncrypt();
 

src/main/java/com/avaje/ebean/config/dbplatform/PostgresPlatform.java

@@ -23,6 +23,7 @@ public class PostgresPlatform extends DatabasePlatform {
   public PostgresPlatform() {
     super();
     this.name = "postgres";
+    this.likeClause = "like ? escape''";
     
     this.dbDdlSyntax = new PostgresDdlSyntax();
     

src/main/java/com/avaje/ebeaninternal/api/SpiExpressionRequest.java

@@ -44,9 +44,14 @@ public interface SpiExpressionRequest {
 	 * Return the ordered list of bind values for all expressions in this request.
 	 */
 	public ArrayList<Object> getBindValues();
-	
-    /**
-     * Increments the parameter index and returns that value.
-     */
-    public int nextParameter();
+
+  /**
+   * Increments the parameter index and returns that value.
+   */
+  public int nextParameter();
+
+  /**
+   * Append a DB Like clause.
+   */
+  public void appendLike();
 }

src/main/java/com/avaje/ebeaninternal/server/core/OrmQueryRequest.java

@@ -71,6 +71,15 @@ public final class OrmQueryRequest<T> extends BeanRequest implements BeanQueryRe
     this.readOnly = query.isReadOnly();
   }
 
+  
+  /**
+   * Return the database platform like clause.
+   */
+  @Override
+  public String getDBLikeClause() {
+    return ebeanServer.getDatabasePlatform().getLikeClause();
+  }
+
   public void executeSecondaryQueries(int defaultQueryBatch) {
     loadContext.executeSecondaryQueries(this, defaultQueryBatch);
   }

src/main/java/com/avaje/ebeaninternal/server/core/SpiOrmQueryRequest.java

@@ -95,4 +95,9 @@ public interface SpiOrmQueryRequest<T> {
      */
     public BeanCollection<T> getFromQueryCache();
 
+    /**
+     * Return the Database platform like clause.
+     */
+    public String getDBLikeClause();
+
 }

src/main/java/com/avaje/ebeaninternal/server/deploy/DeployParser.java

@@ -71,6 +71,9 @@ public abstract class DeployParser {
 			sb.append(deployWord);
 			if (pos < sourceLength) {
 				sb.append(wordTerminator);
+				if (wordTerminator == SINGLE_QUOTE) {
+				  readLiteral();
+				}
 			}
 		}
 

src/main/java/com/avaje/ebeaninternal/server/expression/LikeExpression.java

@@ -53,7 +53,8 @@ class LikeExpression extends AbstractExpression {
     if (type.equals(LikeType.EQUAL_TO)) {
       request.append(" = ? ");
     } else {
-      request.append(" like ? ");
+      // append db platform like clause
+      request.appendLike();
     }
   }
 

src/main/java/com/avaje/ebeaninternal/util/DefaultExpressionRequest.java

@@ -39,6 +39,16 @@ public class DefaultExpressionRequest implements SpiExpressionRequest {
     return s == null ? logicalProp : s;
   }
 
+  /**
+   * Append the database platform like clause.
+   */
+  @Override
+  public void appendLike() {
+    sb.append(" ");
+    sb.append(queryRequest.getDBLikeClause());
+    sb.append(" ");
+  }
+
   /**
    * Increments the parameter index and returns that value.
    */