/**
* Copyright 2008 biaoping.yin
*
* 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.
*/
package org.frameworkset.persitent.util;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.Reader;
import java.io.StringReader;
import java.io.StringWriter;
import java.io.Writer;
import java.util.List;
import java.util.Map;
import bboss.org.apache.velocity.VelocityContext;
import bboss.org.apache.velocity.context.Context;
import bboss.org.apache.velocity.context.InternalContextAdapterImpl;
import bboss.org.apache.velocity.exception.MethodInvocationException;
import bboss.org.apache.velocity.exception.ParseErrorException;
import bboss.org.apache.velocity.exception.ResourceNotFoundException;
import bboss.org.apache.velocity.exception.TemplateInitException;
import bboss.org.apache.velocity.exception.VelocityException;
import bboss.org.apache.velocity.runtime.RuntimeConstants;
import bboss.org.apache.velocity.runtime.directive.Scope;
import bboss.org.apache.velocity.runtime.directive.StopCommand;
import bboss.org.apache.velocity.runtime.parser.ParseException;
import bboss.org.apache.velocity.runtime.parser.node.ASTText;
import bboss.org.apache.velocity.runtime.parser.node.Node;
import bboss.org.apache.velocity.runtime.parser.node.SimpleNode;
import bboss.org.apache.velocity.runtime.resource.Resource;
import bboss.org.apache.velocity.runtime.resource.ResourceManager;
import com.frameworkset.velocity.BBossVelocityUtil;
/**
* <p> SQLTemplate.java</p>
* <p> Description: sql语句模板</p>
* <p> bboss workgroup </p>
* <p> Copyright (c) 2009 </p>
*
* @Date 2012-12-4 下午7:31:55
* @author biaoping.yin
* @version 1.0
*/
public class SQLTemplate extends Resource
{
/*
* The name of the variable to use when placing
* the scope object into the context.
*/
private String scopeName = "template";
private SQLInfo sqlinfo;
private boolean provideScope = false;
private String sql;
private boolean processed;
private VelocityException errorCondition = null;
/** Default constructor */
public SQLTemplate(SQLInfo sqlinfo)
{
super();
this.sqlinfo = sqlinfo;
this.sql = this.sqlinfo.getSql();
this.setName(sqlinfo.getSqlname());
setType(ResourceManager.RESOURCE_SQL);
}
/**
* 根据解析出的语法结构确定sql语句是否是velocity模板
* 如果不是则重置sqlinfo的istpl属性，相关的缓存就可以使用sqlname来作为key
* 同时避免每次都对token进行拼接，提升系统性能
*/
private void rechecksqlistpl()
{
if(data != null)
{
Node[] childrens = ((SimpleNode)data).getChildren();
if(childrens != null && childrens.length > 0)
{
boolean switchcase = true;
for(Node node:childrens)
{
if(!(node instanceof ASTText))
{
switchcase = false;
break;
}
}
if(switchcase)
{
this.sqlinfo.setIstpl(false);
sqlinfo.setMultiparser(false);
}
}
}
}
/**
* gets the named resource as a stream, parses and inits
*
* @return true if successful
* @throws ResourceNotFoundException if template not found
* from any available source.
* @throws ParseErrorException if template cannot be parsed due
* to syntax (or other) error.
* @throws IOException problem reading input stream
*/
public boolean process()
throws ResourceNotFoundException, ParseErrorException
{
if(processed)
return true;
synchronized(this)
{
if(processed)
return true;
data = null;
errorCondition = null;
Reader is = null;
/*
* first, try to get the stream from the loader
*/
try
{
is = new StringReader(sql);
}
catch( ResourceNotFoundException rnfe )
{
/*
* remember and re-throw
*/
errorCondition = rnfe;
processed = true;
throw rnfe;
}
/*
* if that worked, lets protect in case a loader impl
* forgets to throw a proper exception
*/
if (is != null)
{
/*
* now parse the template
*/
try
{
BufferedReader br = new BufferedReader( is);
data = rsvc.parseSQL( br, name);
initDocument();
processed = true;
try {
rechecksqlistpl();
} catch (Exception e) {
}
return true;
}
catch ( ParseException pex )
{
/*
* remember the error and convert
*/
errorCondition = new ParseErrorException(pex, name);
processed = true;
throw errorCondition;
}
catch ( TemplateInitException pex )
{
errorCondition = new ParseErrorException( pex, name);
processed = true;
throw errorCondition;
}
/**
* pass through runtime exceptions
*/
catch( RuntimeException e )
{
errorCondition = new VelocityException("Exception thrown processing Template "
+getName(), e);
processed = true;
throw errorCondition;
}
finally
{
processed = true;
/*
* Make sure to close the inputstream when we are done.
*/
try
{
is.close();
}
catch(IOException e)
{
// If we are already throwing an exception then we want the original
// exception to be continued to be thrown, otherwise, throw a new Exception.
if (errorCondition == null)
{
throw new VelocityException(e);
}
}
}
}
else
{
/*
* is == null, therefore we have some kind of file issue
*/
errorCondition = new ResourceNotFoundException("Unknown resource error for resource " + name );
processed = true;
throw errorCondition;
}
}
}
/**
* initializes the document. init() is not longer
* dependant upon context, but we need to let the
* init() carry the template name down throught for VM
* namespace features
* @throws TemplateInitException When a problem occurs during the document initialization.
*/
public void initDocument()
throws TemplateInitException
{
/*
* send an empty InternalContextAdapter down into the AST to initialize it
*/
InternalContextAdapterImpl ica = new InternalContextAdapterImpl( new VelocityContext() );
try
{
/*
* put the current template name on the stack
*/
ica.pushCurrentTemplateName( name );
ica.setCurrentResource( this );
/*
* init the AST
*/
((SimpleNode)data).init( ica, rsvc);
String property = scopeName+'.'+RuntimeConstants.PROVIDE_SCOPE_CONTROL;
provideScope = rsvc.getBoolean(property, provideScope);
}
finally
{
/*
* in case something blows up...
* pull it off for completeness
*/
ica.popCurrentTemplateName();
ica.setCurrentResource( null );
}
}
/**
* The AST node structure is merged with the
* context to produce the final output.
*
* @param context Conext with data elements accessed by template
* @param writer output writer for rendered template
* @throws ResourceNotFoundException if template not found
* from any available source.
* @throws ParseErrorException if template cannot be parsed due
* to syntax (or other) error.
* @throws MethodInvocationException When a method on a referenced object in the context could not invoked.
*/
public void merge( Context context, Writer writer)
throws ResourceNotFoundException, ParseErrorException, MethodInvocationException
{
merge(context, writer, null);
}
public String evaluate( Map variablevalues)
throws ResourceNotFoundException, ParseErrorException, MethodInvocationException
{
StringWriter writer = new StringWriter();
merge(BBossVelocityUtil.buildVelocityContext(variablevalues), writer, null);
return writer.toString();
}
/**
* The AST node structure is merged with the
* context to produce the final output.
*
* @param context Conext with data elements accessed by template
* @param writer output writer for rendered template
* @param macroLibraries a list of template files containing macros to be used when merging
* @throws ResourceNotFoundException if template not found
* from any available source.
* @throws ParseErrorException if template cannot be parsed due
* to syntax (or other) error.
* @throws MethodInvocationException When a method on a referenced object in the context could not invoked.
* @since 1.6
*/
public void merge( Context context, Writer writer, List macroLibraries)
throws ResourceNotFoundException, ParseErrorException, MethodInvocationException
{
process();
/*
* we shouldn't have to do this, as if there is an error condition,
* the application code should never get a reference to the
* Template
*/
if (errorCondition != null)
{
throw errorCondition;
}
if( data != null)
{
/*
* create an InternalContextAdapter to carry the user Context down
* into the rendering engine. Set the template name and render()
*/
InternalContextAdapterImpl ica = new InternalContextAdapterImpl( context );
/**
* Set the macro libraries
*/
ica.setMacroLibraries(macroLibraries);
if (macroLibraries != null)
{
for (int i = 0; i < macroLibraries.size(); i++)
{
/**
* Build the macro library
*/
try
{
rsvc.getTemplate((String) macroLibraries.get(i));
}
catch (ResourceNotFoundException re)
{
/*
* the macro lib wasn't found. Note it and throw
*/
rsvc.getLog().error("template.merge(): " +
"cannot find template " +
(String) macroLibraries.get(i));
throw re;
}
catch (ParseErrorException pe)
{
/*
* the macro lib was found, but didn't parse - syntax error
* note it and throw
*/
rsvc.getLog().error("template.merge(): " +
"syntax error in template " +
(String) macroLibraries.get(i) + ".");
throw pe;
}
catch (Exception e)
{
throw new RuntimeException("Template.merge(): parse failed in template " +
(String) macroLibraries.get(i) + ".", e);
}
}
}
if (provideScope)
{
ica.put(scopeName, new Scope(this, ica.get(scopeName)));
}
try
{
ica.pushCurrentTemplateName( name );
ica.setCurrentResource( this );
( (SimpleNode) data ).render( ica, writer);
}
catch (StopCommand stop)
{
if (!stop.isFor(this))
{
throw stop;
}
else if (rsvc.getLog().isDebugEnabled())
{
rsvc.getLog().debug(stop.getMessage());
}
}
catch (IOException e)
{
throw new VelocityException("IO Error rendering template '"+ name + "'", e);
}
finally
{
/*
* lets make sure that we always clean up the context
*/
ica.popCurrentTemplateName();
ica.setCurrentResource( null );
if (provideScope)
{
Object obj = ica.get(scopeName);
if (obj instanceof Scope)
{
Scope scope = (Scope)obj;
if (scope.getParent() != null)
{
ica.put(scopeName, scope.getParent());
}
else if (scope.getReplaced() != null)
{
ica.put(scopeName, scope.getReplaced());
}
else
{
ica.remove(scopeName);
}
}
}
}
}
else
{
/*
* this shouldn't happen either, but just in case.
*/
String msg = "Template.merge() failure. The document is null, " +
"most likely due to parsing error.";
throw new RuntimeException(msg);
}
}
}