package org.apache.ojb.broker.metadata;
/* Copyright 2003-2004 The Apache Software Foundation
*
* Licensed 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.
*/
import org.apache.commons.lang.builder.ToStringBuilder;
import org.apache.commons.lang.builder.ToStringStyle;
import org.apache.ojb.broker.accesslayer.conversions.FieldConversion;
import java.io.Serializable;
/**
* An ArgumentDescriptor contains information that defines a single argument
* that is passed to a procedure/function.
* <br>
* Note: Be careful when use ArgumentDescriptor variables or caching
* ArgumentDescriptor instances, because instances could become invalid
* during runtime (see {@link MetadataManager}).
*
* @author <a href="mailto:rongallagher@bellsouth.net">Ron Gallagher<a>
* @version $Id: ArgumentDescriptor.java,v 1.8 2004/06/19 09:21:37 arminw Exp $
*/
public final class ArgumentDescriptor extends DescriptorBase implements XmlCapable, Serializable
{
private static final long serialVersionUID = 5205304260023247711L;
private static final int SOURCE_NULL = 0;
private static final int SOURCE_FIELD = 1;
private static final int SOURCE_VALUE = 2;
private int fieldSource = SOURCE_NULL;
private String constantValue = null;
private String fieldRefName = null;
private boolean returnedByProcedure = false;
//---------------------------------------------------------------
/**
* The procedure descriptor that this object is related to.
*/
private ProcedureDescriptor procedureDescriptor;
//---------------------------------------------------------------
/**
* Constructor declaration. By default, this object will be configured
* so that the value returned by {@link #fieldSource} will be null. To
* change this, call either version of the setValue method.
*
* @see #setValue()
* @see #setValue(String)
* @see #setValue(String,boolean)
*/
public ArgumentDescriptor(ProcedureDescriptor procedureDescriptor)
{
this.procedureDescriptor = procedureDescriptor;
this.setValue();
}
/**
* Sets up this object to represent a null value.
*/
public void setValue()
{
this.fieldSource = SOURCE_NULL;
this.fieldRefName = null;
this.returnedByProcedure = false;
this.constantValue = null;
}
/**
* Sets up this object to represent a value that is derived from a field
* in the corresponding class-descriptor.
* <p>
* If the value of <code>fieldRefName</code> is blank or refers to an
* invalid field reference, then the value of the corresponding argument
* will be set to null. In this case, {@link #getIsReturnedByProcedure}
* will be set to <code>false</code>, regardless of the value of the
* <code>returnedByProcedure</code> argument.
*
* @param fieldRefName the name of the field reference that provides the
* value of this argument.
* @param returnedByProcedure indicates that the value of the argument
* is returned by the procedure that is invoked.
*/
public void setValue(String fieldRefName, boolean returnedByProcedure)
{
this.fieldSource = SOURCE_FIELD;
this.fieldRefName = fieldRefName;
this.returnedByProcedure = returnedByProcedure;
this.constantValue = null;
// If the field reference is not valid, then disregard the value
// of the returnedByProcedure argument.
if (this.getFieldRef() == null)
{
this.returnedByProcedure = false;
}
// If the field reference is not valid, then disregard the value
// of the returnedByProcedure argument.
if (this.getFieldRef() == null)
{
this.returnedByProcedure = false;
}
}
/**
* Sets up this object to represent an argument that will be set to a
* constant value.
*
* @param constantValue the constant value.
*/
public void setValue(String constantValue)
{
this.fieldSource = SOURCE_VALUE;
this.fieldRefName = null;
this.returnedByProcedure = false;
this.constantValue = constantValue;
}
public boolean getIsReturnedByProcedure()
{
return this.returnedByProcedure;
}
public Object getValue(Object objekt)
{
switch (this.fieldSource)
{
case SOURCE_FIELD :
if (objekt == null)
{
return null;
}
else
{
FieldDescriptor fd = this.getFieldRef();
Object value = null;
FieldConversion conversion = null;
if (fd != null)
{
conversion = fd.getFieldConversion();
value = fd.getPersistentField().get(objekt);
if (conversion != null)
{
value = conversion.javaToSql(value);
}
}
return value;
}
case SOURCE_VALUE :
return this.constantValue;
case SOURCE_NULL :
return null;
default :
return null;
}
}
public void saveValue(Object objekt, Object value)
{
if ((this.fieldSource == SOURCE_FIELD) && (this.returnedByProcedure))
{
FieldDescriptor fd = this.getFieldRef();
FieldConversion conversion = null;
if (fd != null)
{
conversion = fd.getFieldConversion();
if (conversion == null)
{
fd.getPersistentField().set(objekt, value);
}
else
{
fd.getPersistentField().set(objekt, conversion.sqlToJava(value));
}
}
}
}
//---------------------------------------------------------------
/**
* Retrieve the field descriptor that this argument is related to.
* <p>
* This reference can only be set via the {@link #setValue(String,boolean)}
* method.
* @return The current value
*/
public final FieldDescriptor getFieldRef()
{
if (this.fieldSource == SOURCE_FIELD)
{
return this.getProcedureDescriptor().getClassDescriptor().getFieldDescriptorByName(
this.fieldRefName);
}
else
{
return null;
}
}
/**
* Retrieve the jdbc type for the field descriptor that is related
* to this argument.
*/
public final int getJdbcType()
{
switch (this.fieldSource)
{
case SOURCE_FIELD :
return this.getFieldRef().getJdbcType().getType();
case SOURCE_NULL :
return java.sql.Types.NULL;
case SOURCE_VALUE :
return java.sql.Types.VARCHAR;
default :
return java.sql.Types.NULL;
}
}
//---------------------------------------------------------------
/**
* Retrieve the procedure descriptor that this object is related to.
*
* @return The current value
*/
public final ProcedureDescriptor getProcedureDescriptor()
{
return this.procedureDescriptor;
}
/*
* @see XmlCapable#toXML()
*/
public String toXML()
{
String eol = System.getProperty("line.separator");
RepositoryTags tags = RepositoryTags.getInstance();
// The result
String result = " ";
switch (this.fieldSource)
{
case SOURCE_FIELD :
result += " " + tags.getOpeningTagNonClosingById(RUNTIME_ARGUMENT);
result += " " + tags.getAttribute(FIELD_REF, this.fieldRefName);
result += " " + tags.getAttribute(RETURN, String.valueOf(this.returnedByProcedure));
result += "/>";
break;
case SOURCE_VALUE :
result += " " + tags.getOpeningTagNonClosingById(CONSTANT_ARGUMENT);
result += " " + tags.getAttribute(VALUE, this.constantValue);
result += "/>";
break;
case SOURCE_NULL :
result += " " + tags.getOpeningTagNonClosingById(RUNTIME_ARGUMENT);
result += "/>";
break;
default :
break;
}
// Return the result.
return (result + eol);
}
//---------------------------------------------------------------
/**
* Provide a string representation of this object
*
* @return a string representation of this object
*/
public String toString()
{
ToStringBuilder buf = new ToStringBuilder(this, ToStringStyle.MULTI_LINE_STYLE);
switch (this.fieldSource)
{
case SOURCE_FIELD :
{
buf.append("fieldRefName", this.fieldRefName);
buf.append("returnedByProcedure", this.returnedByProcedure);
break;
}
case SOURCE_NULL :
{
break;
}
case SOURCE_VALUE :
{
buf.append("constantValue", this.constantValue);
break;
}
}
return buf.toString();
}
}