/* | |
* Licensed to the Apache Software Foundation (ASF) under one | |
* or more contributor license agreements. See the NOTICE file | |
* distributed with this work for additional information | |
* regarding copyright ownership. The ASF licenses this file | |
* to you under the Apache License, Version 2.0 (the | |
* "License"); you may not use this file except in compliance | |
* with the License. You may obtain a copy of the License at | |
* | |
* http://www.apache.org/licenses/LICENSE-2.0 | |
* | |
* Unless required by applicable law or agreed to in writing, | |
* software distributed under the License is distributed on an | |
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY | |
* KIND, either express or implied. See the License for the | |
* specific language governing permissions and limitations | |
* under the License. | |
*/ | |
package org.apache.empire.jsf2.app; | |
import java.beans.FeatureDescriptor; | |
import java.lang.reflect.Field; | |
import java.util.Iterator; | |
import javax.el.ELContext; | |
import javax.el.ELResolver; | |
import javax.faces.context.FacesContext; | |
import org.apache.empire.commons.StringUtils; | |
import org.apache.empire.data.Record; | |
import org.apache.empire.data.RecordData; | |
import org.apache.empire.db.DBColumnExpr; | |
import org.apache.empire.db.DBDatabase; | |
import org.apache.empire.db.DBRowSet; | |
import org.apache.empire.exceptions.NotSupportedException; | |
import org.slf4j.Logger; | |
import org.slf4j.LoggerFactory; | |
public class DBELResolver extends ELResolver | |
{ | |
private static final Logger log = LoggerFactory.getLogger(DBELResolver.class); | |
@Override | |
public Class<?> getCommonPropertyType(ELContext context, Object base) | |
{ | |
if (base==null) | |
log.warn("DBELResolver:getCommonPropertyType is not implemented!"); | |
return null; | |
} | |
@Override | |
public Class<?> getType(ELContext context, Object base, Object property) | |
{ | |
if ((base instanceof DBRowSet) || | |
(base instanceof DBDatabase) || | |
(base==null && property.equals("db"))) | |
log.warn("DBELResolver:getType is not implemented!"); | |
return null; | |
} | |
@Override | |
public Iterator<FeatureDescriptor> getFeatureDescriptors(ELContext arg0, Object arg1) | |
{ | |
log.warn("DBELResolver:getFeatureDescriptors is not implemented!"); | |
return null; | |
} | |
@Override | |
public Object getValue(ELContext context, Object base, Object property) | |
{ | |
// Resolve database, table/view or column | |
if (base instanceof DBRowSet) | |
{ // Find matching column | |
String name = StringUtils.toString(property); | |
DBColumnExpr column = ((DBRowSet)base).getColumn(name); | |
if (column==null) | |
column = findExpressionField(base, name); | |
if (column!=null) | |
context.setPropertyResolved(true); | |
else | |
log.error("ELResolver error: Column '{}' cannot be resolved for table/view '{}'.", name.toUpperCase(), ((DBRowSet)base).getName()); | |
// done | |
return column; | |
} | |
else if (base instanceof DBDatabase) | |
{ // Lookup RowSet | |
String name = StringUtils.toString(property); | |
DBRowSet rset = ((DBDatabase)base).getRowSet(name); | |
if (rset!=null) | |
context.setPropertyResolved(true); | |
else | |
log.error("ELResolver error: Table/View '{}' cannot be resolved.", name.toUpperCase()); | |
// done | |
return rset; | |
} | |
else if (base instanceof RecordData) | |
{ // Lookup RowSet | |
String field= StringUtils.toString(property); | |
// field must start with a capital Letter | |
if (field==null || field.length()==0 || field.charAt(0)<'A' || field.charAt(0)>'Z') | |
return null; | |
// try to find field | |
int index = ((Record)base).getFieldIndex(field); | |
if (index<0) | |
{ // not a field, it may be a property | |
log.warn("ELResolver warning: field '{}' not found in record .", field); | |
// not resolved, continue search | |
return null; | |
} | |
// Found! Return field value. | |
context.setPropertyResolved(true); | |
return ((Record)base).getValue(index); | |
} | |
else if (base==null) | |
{ // LookupDatabase | |
String name = StringUtils.toString(property); | |
DBDatabase db = DBDatabase.findById(name); | |
if (db!=null) | |
context.setPropertyResolved(true); | |
// done | |
return db; | |
} | |
return null; | |
} | |
public static DBColumnExpr findExpressionField(Object rowset, String property) | |
{ | |
Class<?> c = rowset.getClass(); | |
try | |
{ // Find a matching field name | |
Field f = c.getField(property); | |
if (f==null) | |
return null; | |
Object v = f.get(rowset); | |
if (v==null) | |
{ // invalid data type | |
log.error("ELResolver error: Field '{}.{}' is null.", c.getSimpleName(), property); | |
return null; | |
} | |
if (!(v instanceof DBColumnExpr)) | |
{ // invalid data type | |
log.error("ELResolver error: Field '{}.{}' is not a DBColumnExpr.", c.getSimpleName(), property); | |
return null; | |
} | |
return ((DBColumnExpr)v); | |
} | |
catch (SecurityException e) | |
{ | |
log.error("ELResolver error: Unable to access field "+c.getSimpleName()+"."+property, e); | |
return null; | |
} | |
catch (NoSuchFieldException e) | |
{ | |
return null; | |
} | |
catch (IllegalArgumentException e) | |
{ | |
log.error("ELResolver error: Unable to access field "+c.getSimpleName()+"."+property, e); | |
return null; | |
} | |
catch (IllegalAccessException e) | |
{ | |
log.error("ELResolver error: Unable to access field "+c.getSimpleName()+"."+property, e); | |
return null; | |
} | |
} | |
@Override | |
public boolean isReadOnly(ELContext context, Object base, Object property) | |
{ | |
// is it our's? | |
if ((base instanceof DBRowSet) || | |
(base instanceof DBDatabase) || | |
(base==null && property.equals("db"))) | |
{ // read only | |
log.info("ELResolver: property {} is read only.", property); | |
return true; | |
} | |
// not our business | |
return false; | |
} | |
@Override | |
public void setValue(ELContext context, Object base, Object property, Object value) | |
{ | |
if (isReadOnly(context, base, property)) | |
{ | |
RuntimeException e = new NotSupportedException(this, "setValue"); | |
FacesContext.getCurrentInstance().getExternalContext().log(e.getMessage(), e); | |
throw e; | |
} | |
} | |
} |