/*
* Copyright 2005 Red Hat, Inc. and/or its affiliates.
*
* 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.drools.template.parser;
import org.drools.core.util.IoUtils;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
* Container for a set of templates (residing in one file). This class will
* parse the template file.
*/
public class DefaultTemplateContainer implements TemplateContainer {
private String header;
private Map<String, Column> columnMap = new HashMap<String, Column>();
private List<Column> columns = new ArrayList<Column>();
private Map<String, RuleTemplate> templates = new HashMap<String, RuleTemplate>();
private boolean replaceOptionals;
public DefaultTemplateContainer(final String template) {
this(DefaultTemplateContainer.class.getResourceAsStream(template), true);
}
public DefaultTemplateContainer(final InputStream templateStream) {
this(templateStream, true);
}
public DefaultTemplateContainer(final String template, boolean replaceOptionals) {
this(DefaultTemplateContainer.class.getResourceAsStream(template), replaceOptionals);
}
public DefaultTemplateContainer(final InputStream templateStream, boolean replaceOptionals) {
this.replaceOptionals = replaceOptionals;
parseTemplate(templateStream);
validateTemplate();
}
private void validateTemplate() {
if (columns.size() == 0) {
throw new DecisionTableParseException("Missing header columns");
}
if (templates.size() == 0) {
throw new DecisionTableParseException("Missing templates");
}
}
private void parseTemplate(final InputStream templateStream) {
try {
final ColumnFactory cf = new ColumnFactory();
final BufferedReader templateReader = new BufferedReader(
new InputStreamReader(templateStream, IoUtils.UTF8_CHARSET));
String line;
boolean inTemplate = false;
boolean inHeader = false;
boolean inContents = false;
boolean inMultiLineComment = false;
RuleTemplate template = null;
StringBuilder header = new StringBuilder();
StringBuilder contents = new StringBuilder();
while ((line = templateReader.readLine()) != null) {
if (inMultiLineComment) {
int commentEnd = line.indexOf( "*/" );
if (commentEnd >= 0) {
line = line.substring( commentEnd+2 );
inMultiLineComment = false;
} else {
line = "";
}
} else {
int commentStart = line.indexOf( "/*" );
if (commentStart >= 0) {
int commentEnd = line.indexOf( "*/" );
if (commentEnd > commentStart) {
line = line.substring( 0, commentStart ) + line.substring( commentEnd+2 );
} else {
line = line.substring( 0, commentStart );
inMultiLineComment = true;
}
}
}
String trimmed = line.trim();
if (trimmed.length() > 0) {
if (trimmed.startsWith("template header")) {
inHeader = true;
} else if (trimmed.startsWith("template")) {
inTemplate = true;
inHeader = false;
String quotedName = trimmed.substring(8).trim();
quotedName = quotedName.substring(1, quotedName.length() - 1);
template = new RuleTemplate(quotedName, this, replaceOptionals );
addTemplate(template);
} else if (trimmed.startsWith("package")) {
if ( !inHeader ) {
throw new DecisionTableParseException(
"Missing header");
}
inHeader = false;
header.append(line).append("\n");
} else if (trimmed.startsWith("import")) {
inHeader = false;
header.append(line).append("\n");
} else if (inHeader) {
addColumn(cf.getColumn(trimmed));
} else if (!inTemplate) {
header.append(line).append("\n");
} else if (!inContents && trimmed.startsWith("rule")) {
inContents = true;
contents.append(line).append("\n");
} else if (trimmed.equals("end template")) {
template.setContents(contents.toString());
contents.setLength(0);
inTemplate = false;
inContents = false;
} else if (inContents) {
contents.append(removeSingleLineComment(line)).append( "\n");
} else {
template.addColumn(trimmed);
}
}
}
if (inTemplate) {
throw new DecisionTableParseException("Missing end template");
}
this.header = header.toString();
} catch (IOException e) {
throw new RuntimeException(e);
} finally {
if (templateStream != null) { closeStream(templateStream); }
}
}
private String removeSingleLineComment(String line) {
int commentStart = line.indexOf( "//" );
return commentStart < 0 ? line : line.substring( 0, commentStart );
}
private void addTemplate(RuleTemplate template) {
templates.put(template.getName(), template);
}
/*
* (non-Javadoc)
*
* @see org.kie.decisiontable.parser.TemplateContainer#getTemplates()
*/
public Map<String, RuleTemplate> getTemplates() {
return templates;
}
private void addColumn(Column c) {
columns.add(c);
columnMap.put(c.getName(), c);
}
/*
* (non-Javadoc)
*
* @see org.kie.decisiontable.parser.TemplateContainer#getColumns()
*/
public Column[] getColumns() {
return columns.toArray(new Column[columns.size()]);
}
/*
* (non-Javadoc)
*
* @see org.kie.decisiontable.parser.TemplateContainer#getHeader()
*/
public String getHeader() {
return header;
}
private void closeStream(final InputStream stream) {
try {
stream.close();
} catch (final Exception e) {
System.err.print("WARNING: Wasn't able to "
+ "correctly close stream for decision table. "
+ e.getMessage());
}
}
public Column getColumn(final String name) {
return columnMap.get(name);
}
}