/*
* Copyright 2014 Attila Szegedi, Daniel Dekany, Jonathan Revusky
*
* 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 freemarker.ext.servlet;
import java.io.File;
import java.io.IOException;
import java.text.ParseException;
import java.util.ArrayList;
import java.util.List;
import java.util.regex.Pattern;
import javax.servlet.ServletContext;
import freemarker.cache.ClassTemplateLoader;
import freemarker.cache.FileTemplateLoader;
import freemarker.cache.MultiTemplateLoader;
import freemarker.cache.TemplateLoader;
import freemarker.cache.WebappTemplateLoader;
import freemarker.core._ObjectBuilderSettingEvaluator;
import freemarker.core._SettingEvaluationEnvironment;
import freemarker.log.Logger;
import freemarker.template.Configuration;
import freemarker.template._TemplateAPI;
import freemarker.template.utility.StringUtil;
final class InitParamParser {
static final String TEMPLATE_PATH_PREFIX_CLASS = "class://";
static final String TEMPLATE_PATH_PREFIX_CLASSPATH = "classpath:";
static final String TEMPLATE_PATH_PREFIX_FILE = "file://";
static final String TEMPLATE_PATH_SETTINGS_BI_NAME = "settings";
private static final Logger LOG = Logger.getLogger("freemarker.servlet");
private InitParamParser() {
// Not to be instantiated
}
static TemplateLoader createTemplateLoader(
String templatePath, Configuration cfg, Class classLoaderClass, ServletContext srvCtx)
throws IOException {
final int settingAssignmentsStart = findTemplatePathSettingAssignmentsStart(templatePath);
String pureTemplatePath = (settingAssignmentsStart == -1 ? templatePath : templatePath.substring(0, settingAssignmentsStart))
.trim();
final TemplateLoader templateLoader;
if (pureTemplatePath.startsWith(TEMPLATE_PATH_PREFIX_CLASS)) {
String packagePath = pureTemplatePath.substring(TEMPLATE_PATH_PREFIX_CLASS.length());
packagePath = normalizeToAbsolutePackagePath(packagePath);
templateLoader = new ClassTemplateLoader(classLoaderClass, packagePath);
} else if (pureTemplatePath.startsWith(TEMPLATE_PATH_PREFIX_CLASSPATH)) {
// To be similar to Spring resource paths, we don't require "//":
String packagePath = pureTemplatePath.substring(TEMPLATE_PATH_PREFIX_CLASSPATH.length());
packagePath = normalizeToAbsolutePackagePath(packagePath);
ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
if (classLoader == null) {
LOG.warn("No Thread Context Class Loader was found. Falling back to the class loader of "
+ classLoaderClass.getName() + ".");
classLoader = classLoaderClass.getClassLoader();
}
templateLoader = new ClassTemplateLoader(classLoader, packagePath);
} else if (pureTemplatePath.startsWith(TEMPLATE_PATH_PREFIX_FILE)) {
String filePath = pureTemplatePath.substring(TEMPLATE_PATH_PREFIX_FILE.length());
templateLoader = new FileTemplateLoader(new File(filePath));
} else if (pureTemplatePath.startsWith("[")
&& cfg.getIncompatibleImprovements().intValue() >= _TemplateAPI.VERSION_INT_2_3_22) {
if (!pureTemplatePath.endsWith("]")) {
// B.C. constraint: Can't throw any checked exceptions.
throw new TemplatePathParsingException("Failed to parse template path; closing \"]\" is missing.");
}
String commaSepItems = pureTemplatePath.substring(1, pureTemplatePath.length() - 1).trim();
List listItems = parseCommaSeparatedTemplatePaths(commaSepItems);
TemplateLoader[] templateLoaders = new TemplateLoader[listItems.size()];
for (int i = 0; i < listItems.size(); i++) {
String pathItem = (String) listItems.get(i);
templateLoaders[i] = createTemplateLoader(pathItem, cfg, classLoaderClass, srvCtx);
}
templateLoader = new MultiTemplateLoader(templateLoaders);
} else if (pureTemplatePath.startsWith("{")
&& cfg.getIncompatibleImprovements().intValue() >= _TemplateAPI.VERSION_INT_2_3_22) {
throw new TemplatePathParsingException("Template paths starting with \"{\" are reseved for future purposes");
} else {
templateLoader = new WebappTemplateLoader(srvCtx, pureTemplatePath);
}
if (settingAssignmentsStart != -1) {
try {
int nextPos = _ObjectBuilderSettingEvaluator.configureBean(
templatePath, templatePath.indexOf('(', settingAssignmentsStart) + 1, templateLoader,
_SettingEvaluationEnvironment.getCurrent());
if (nextPos != templatePath.length()) {
throw new TemplatePathParsingException("Template path should end after the setting list in: "
+ templatePath);
}
} catch (Exception e) {
throw new TemplatePathParsingException("Failed to set properties in: " + templatePath, e);
}
}
return templateLoader;
}
static String normalizeToAbsolutePackagePath(String path) {
while (path.startsWith("/")) {
path = path.substring(1);
}
return "/" + path;
}
static List/*<String>*/ parseCommaSeparatedList(String value) throws ParseException {
List/*<String>*/ valuesList = new ArrayList();
String[] values = StringUtil.split(value, ',');
for (int i = 0; i < values.length; i++) {
final String s = values[i].trim();
if (s.length() != 0) {
valuesList.add(s);
} else if (i != values.length - 1) {
throw new ParseException("Missing list item berfore a comma", -1);
}
}
return valuesList;
}
static List parseCommaSeparatedPatterns(String value) throws ParseException {
List/*<String>*/ values = parseCommaSeparatedList(value);
List/*<Pattern>*/ patterns = new ArrayList(values.size());
for (int i = 0; i < values.size(); i++) {
patterns.add(Pattern.compile((String) values.get(i)));
}
return patterns;
}
/**
* This is like {@link #parseCommaSeparatedList(String)}, but is not confused by commas inside
* {@code ?settings(...)} parts at the end of the items.
*/
static List parseCommaSeparatedTemplatePaths(String commaSepItems) {
List listItems;
listItems = new ArrayList();
while (commaSepItems.length() != 0) {
int itemSettingAssignmentsStart = findTemplatePathSettingAssignmentsStart(commaSepItems);
int pureItemEnd = itemSettingAssignmentsStart != -1 ? itemSettingAssignmentsStart : commaSepItems.length();
int prevComaIdx = commaSepItems.lastIndexOf(',', pureItemEnd - 1);
int itemStart = prevComaIdx != -1 ? prevComaIdx + 1 : 0;
final String item = commaSepItems.substring(itemStart).trim();
if (item.length() != 0) {
listItems.add(0, item);
} else if (listItems.size() > 0) {
throw new TemplatePathParsingException("Missing list item before a comma");
}
commaSepItems = prevComaIdx != -1 ? commaSepItems.substring(0, prevComaIdx).trim() : "";
}
return listItems;
}
/**
* @return -1 if there's no setting assignment.
*/
static int findTemplatePathSettingAssignmentsStart(String s) {
int pos = s.length() - 1;
// Skip WS
while (pos >= 0 && Character.isWhitespace(s.charAt(pos))) {
pos--;
}
// Skip `)`
if (pos < 0 || s.charAt(pos) != ')') return -1;
pos--;
// Skip `(...`
int parLevel = 1;
int mode = 0;
while (parLevel > 0) {
if (pos < 0) return -1;
char c = s.charAt(pos);
switch (mode) {
case 0: // 0: outside string literal
switch (c) {
case '(': parLevel--; break;
case ')': parLevel++; break;
case '\'': mode = 1; break;
case '"': mode = 2; break;
}
break;
case 1: // 1: inside '...'
if (c == '\'' && !(pos > 0 && s.charAt(pos - 1) == '\\')) {
mode = 0;
}
break;
case 2: // 2: inside "..."
if (c == '"' && !(pos > 0 && s.charAt(pos - 1) == '\\')) {
mode = 0;
}
break;
}
pos--;
}
// Skip WS
while (pos >= 0 && Character.isWhitespace(s.charAt(pos))) {
pos--;
}
int biNameEnd = pos + 1;
// Skip name chars
while (pos >= 0 && Character.isJavaIdentifierPart(s.charAt(pos))) {
pos--;
}
int biNameStart = pos + 1;
if (biNameStart == biNameEnd) {
return -1;
}
String biName = s.substring(biNameStart, biNameEnd);
// Skip WS
while (pos >= 0 && Character.isWhitespace(s.charAt(pos))) {
pos--;
}
// Skip `?`
if (pos < 0 || s.charAt(pos) != '?') return -1;
if (!biName.equals(TEMPLATE_PATH_SETTINGS_BI_NAME)) {
throw new TemplatePathParsingException(
StringUtil.jQuote(biName) + " is unexpected after the \"?\". "
+ "Expected \"" + TEMPLATE_PATH_SETTINGS_BI_NAME + "\".");
}
return pos;
}
private static final class TemplatePathParsingException extends RuntimeException {
public TemplatePathParsingException(String message, Throwable cause) {
super(message, cause);
}
public TemplatePathParsingException(String message) {
super(message);
}
}
}