add initial ColumnValidator support

git-svn-id: https://svn.code.sf.net/p/jackcess/code/jackcess/trunk@849 f203690c-595d-4dc9-a70b-905162fa7fd2

4 files changed, 158 insertions, 0 deletions

diff --git a/src/main/java/com/healthmarketscience/jackcess/util/ColumnValidator.java b/src/main/java/com/healthmarketscience/jackcess/util/ColumnValidator.java
new file mode 100644
index 0000000..50c8916
--- /dev/null
+++ b/src/main/java/com/healthmarketscience/jackcess/util/ColumnValidator.java
@@ -0,0 +1,41 @@
+/*
+Copyright (c) 2014 James Ahlborn
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
+USA
+
+*/
+
+package com.healthmarketscience.jackcess.util;
+
+import java.io.IOException;
+
+import com.healthmarketscience.jackcess.Column;
+
+/**
+ * Interface which allows for data manipulation/validation as values are being
+ * inserted into a database.
+ *
+ * @author James Ahlborn
+ */
+public interface ColumnValidator 
+{
+  /**
+   * Validates and/or manipulates the given potential new value for the given
+   * column.  This method may return an entirely different value or throw an
+   * exception if the input value is not valid.
+   */
+  public Object validate(Column col, Object val) throws IOException;
+}
diff --git a/src/main/java/com/healthmarketscience/jackcess/util/ColumnValidatorFactory.java b/src/main/java/com/healthmarketscience/jackcess/util/ColumnValidatorFactory.java
new file mode 100644
index 0000000..3a8a323
--- /dev/null
+++ b/src/main/java/com/healthmarketscience/jackcess/util/ColumnValidatorFactory.java
@@ -0,0 +1,38 @@
+/*
+Copyright (c) 2014 James Ahlborn
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
+USA
+
+*/
+
+package com.healthmarketscience.jackcess.util;
+
+import com.healthmarketscience.jackcess.Column;
+
+/**
+ * Factory which generates appropriate ColumnValidators when Column instances
+ * are created.
+ *
+ * @author James Ahlborn
+ */
+public interface ColumnValidatorFactory 
+{
+  /**
+   * Returns a ColumnValidator instance for the given column, must be
+   * non-{@code null}.
+   */
+  public ColumnValidator createValidator(Column col);
+}
diff --git a/src/main/java/com/healthmarketscience/jackcess/util/SimpleColumnValidator.java b/src/main/java/com/healthmarketscience/jackcess/util/SimpleColumnValidator.java
new file mode 100644
index 0000000..7dd8817
--- /dev/null
+++ b/src/main/java/com/healthmarketscience/jackcess/util/SimpleColumnValidator.java
@@ -0,0 +1,40 @@
+/*
+Copyright (c) 2014 James Ahlborn
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
+USA
+
+*/
+
+package com.healthmarketscience.jackcess.util;
+
+import java.io.IOException;
+
+import com.healthmarketscience.jackcess.Column;
+
+/**
+ * Simple concrete implementation of ColumnValidator which simply returns the
+ * given value.
+ *
+ * @author James Ahlborn
+ */
+public class SimpleColumnValidator implements ColumnValidator
+{
+  public static final SimpleColumnValidator INSTANCE = new SimpleColumnValidator();
+  
+  public Object validate(Column col, Object val) throws IOException {
+    return val;
+  }
+}
diff --git a/src/main/java/com/healthmarketscience/jackcess/util/SimpleColumnValidatorFactory.java b/src/main/java/com/healthmarketscience/jackcess/util/SimpleColumnValidatorFactory.java
new file mode 100644
index 0000000..367f8c7
--- /dev/null
+++ b/src/main/java/com/healthmarketscience/jackcess/util/SimpleColumnValidatorFactory.java
@@ -0,0 +1,39 @@
+/*
+Copyright (c) 2014 James Ahlborn
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
+USA
+
+*/
+
+package com.healthmarketscience.jackcess.util;
+
+import com.healthmarketscience.jackcess.Column;
+
+/**
+ * Simple concrete implementation of ColumnValidatorFactory which returns
+ * {@link SimpleColumnValidator.INSTANCE} for all columns.
+ *
+ * @author James Ahlborn
+ */
+public class SimpleColumnValidatorFactory implements ColumnValidatorFactory
+{
+  public static final SimpleColumnValidatorFactory INSTANCE =
+    new SimpleColumnValidatorFactory();
+  
+  public ColumnValidator createValidator(Column col) {
+    return SimpleColumnValidator.INSTANCE;
+  }
+}