/**
* Copyright (C) 2008 http://code.google.com/p/maven-license-plugin/
*
* 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 com.google.code.mojo.license.header;
import com.google.code.mojo.license.HeaderSection;
import com.google.code.mojo.license.util.StringUtils;
import java.net.URL;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.SortedMap;
import java.util.TreeMap;
import static com.google.code.mojo.license.util.FileUtils.read;
import static com.google.code.mojo.license.util.FileUtils.remove;
/**
* The <code>Header</code> class wraps the license template file, the one which have to be outputted inside the other
* files.
*
* @author Mathieu Carbou (mathieu.carbou@gmail.com)
*/
public final class Header {
private final URL location;
private final String headerContent;
private final String headerContentOneLine;
private String[] lines;
private final HeaderSection[] sections;
private static final Map<String, String> EMPTY_PROPERTIES = new HashMap<String, String>(0);
/**
* Constructs a <code>Header</code> object pointing to a license template file. In case of the template contains
* replaceable values (declared as ${<em>valuename</em>}), you can set the map of this values.
*
* @param location The license template file location.
* @param properties The map of values to replace.
* @param sections Any applicable header sections for this header
* @throws IllegalArgumentException If the header file location is null or if an error occurred while reading the
* file content.
*/
public Header(URL location, Map<String, String> properties, HeaderSection[] sections) {
if (location == null) {
throw new IllegalArgumentException("Cannot read license template header file with a null location");
}
if (properties == null) {
properties = EMPTY_PROPERTIES;
}
this.location = location;
this.sections = sections;
try {
this.headerContent = read(location, properties);
lines = headerContent.replace("\r", "").split("\n");
headerContentOneLine = remove(headerContent, " ", "\t", "\r", "\n");
}
catch (Exception e) {
throw new IllegalArgumentException("Cannot read header document " + location + ". Cause: " + e.getMessage(), e);
}
}
public String asString() {
return headerContent;
}
public String asOneLineString() {
return headerContentOneLine;
}
public int getLineCount() {
return lines.length;
}
/**
* Returns the location of license template file.
*
* @return The URL location.
*/
public URL getLocation() {
return location;
}
public String eol(boolean unix) {
return unix ? "\n" : "\r\n";
}
public String buildForDefinition(HeaderDefinition type, boolean unix) {
StringBuilder newHeader = new StringBuilder();
if (notEmpty(type.getFirstLine())) {
newHeader.append(type.getFirstLine().replace("EOL", eol(unix)));
newHeader.append(eol(unix));
}
for (String line : getLines()) {
final String str = type.getBeforeEachLine().replace("EOL", eol(unix)) + line;
newHeader.append(StringUtils.rtrim(str));
newHeader.append(eol(unix));
}
if (notEmpty(type.getEndLine())) {
newHeader.append(type.getEndLine().replace("EOL", eol(unix)));
newHeader.append(eol(unix));
}
return newHeader.toString();
}
@Override
public String toString() {
return asString();
}
public String[] getLines() {
return lines;
}
/**
* Determines if a potential file header (typically, the start of the file
* plus some buffer space) matches this header, as rendered with the
* specified {@link HeaderDefinition} and line-ending.
*
* @param potentialFileHeader
* the potential file header, usually with some extra buffer
* lines
* @param headerDefinition
* the header definition to render the header with
* @param unix
* if true, unix line-endings will be used
* @return true if the header is matched
*/
public boolean isMatchForText(String potentialFileHeader, HeaderDefinition headerDefinition, boolean unix) {
String expected = buildForDefinition(headerDefinition, unix);
SortedMap<Integer, HeaderSection> sectionsByIndex = computeSectionsByIndex(expected);
if (sectionsByIndex.isEmpty())
return potentialFileHeader.contains(expected);
List<String> textBetweenSections = buildExpectedTextBetweenSections(expected, sectionsByIndex);
List<HeaderSection> sectionsInOrder = new ArrayList<HeaderSection>(sectionsByIndex.values());
return recursivelyFindMatch(potentialFileHeader, headerDefinition, textBetweenSections, sectionsInOrder, 0, 0);
}
public String applyDefinitionAndSections(HeaderDefinition headerDefinition, boolean unix) {
String expected = buildForDefinition(headerDefinition, unix);
SortedMap<Integer, HeaderSection> sectionsByIndex = computeSectionsByIndex(expected);
if (sectionsByIndex.isEmpty())
return expected;
List<String> textBetweenSections = buildExpectedTextBetweenSections(expected, sectionsByIndex);
List<HeaderSection> sectionsInOrder = new ArrayList<HeaderSection>(sectionsByIndex.values());
StringBuilder b = new StringBuilder();
for( int i=0; i<textBetweenSections.size();++i) {
String textBetween = textBetweenSections.get(i);
b.append(textBetween);
if( i < sectionsInOrder.size() ) {
HeaderSection section = sectionsInOrder.get(i);
String sectionValue = section.getDefaultValue();
if( notEmpty(sectionValue)) {
String[] tokens = sectionValue.split(eol(unix));
for( int j=0;j<tokens.length; j++) {
if (j > 0) {
b.append(eol(unix));
if (notEmpty(headerDefinition.getBeforeEachLine()))
b.append(headerDefinition.getBeforeEachLine());
}
b.append(tokens[j]);
}
}
}
}
return b.toString();
}
private boolean notEmpty(String str) {
return str != null && str.length() > 0;
}
/**
* If this Header has any {@link HeaderSection} sections defined, we look
* for each header key in the expected header text and note the position
* index of the match.
*
* @param expectedHeaderText
* the expected header text
* @return a sorted-map of matching HeaderSections, with the key being the
* index of section in the header text
*/
private SortedMap<Integer, HeaderSection> computeSectionsByIndex(String expectedHeaderText) {
SortedMap<Integer, HeaderSection> sectionsByIndex = new TreeMap<Integer, HeaderSection>();
if (sections == null)
return sectionsByIndex;
for (HeaderSection section : sections) {
String key = section.getKey();
int index = expectedHeaderText.indexOf(key);
if (index == -1) {
// TODO: we need some way to log that a header section key was
// not found...
continue;
}
/**
* Verify that the new section doesn't overlap with an existing
* section
*/
int indexEnd = index + section.getKey().length();
for (Map.Entry<Integer, HeaderSection> entry : sectionsByIndex.entrySet()) {
int existingIndexStart = entry.getKey();
HeaderSection existingSection = entry.getValue();
int existingIndexEnd = existingIndexStart + existingSection.getKey().length();
if (existingIndexStart < indexEnd && index < existingIndexEnd)
throw new IllegalArgumentException(String.format(
"Existing section '%1$s' overlaps with new section '%2$s'", existingSection.getKey(),
section.getKey()));
sectionsByIndex.put(index, section);
}
sectionsByIndex.put(index, section);
}
return sectionsByIndex;
}
/**
* Once we have found the set of header sections indexed in the expected
* header text, we extract out the remaining header text occurring
* in-between those header sections and return an ordered list of the
* segments.
*
* As an example, if out text looked like:
*
* "My name is NAME_SECTION and I work for COMPANY_SECTION most days."
*
* where "NAME_SECTION" and "COMPANY_SECTION" are matched sections, the
* resulting list should look like:
*
* ["My name is ", " and I work for ", " most days."]
*
* @param expectedHeaderText
* the expected header text
* @param sectionsByIndex
* a sorted-map of matching HeaderSections, with the key being
* the index of section in the header text
* @return an ordered list of the text segments occurring in-between the
* sections
*/
private List<String> buildExpectedTextBetweenSections(String expectedHeaderText,
SortedMap<Integer, HeaderSection> sectionsByIndex) {
List<String> textBetweenSections = new ArrayList<String>();
int currentIndex = 0;
for (Map.Entry<Integer, HeaderSection> entry : sectionsByIndex.entrySet()) {
int index = entry.getKey();
HeaderSection section = entry.getValue();
String textBetween = expectedHeaderText.substring(currentIndex, index);
textBetweenSections.add(textBetween);
currentIndex = index + section.getKey().length();
}
/**
* Add the tail of the expected text
*/
String textBetween = expectedHeaderText.substring(currentIndex, expectedHeaderText.length());
textBetweenSections.add(textBetween);
return textBetweenSections;
}
/**
* Given a potential file header and our expected segmented header text,
* this method recursively searches through the expected segments, looking
* for possible matches.
*
* We recursively search through the potential header for each of the
* expected text section, advancing our current text segment index and our
* index into the potential header text. Each step of the recursion
* considers all possible matches for a text segment, such that the
* recursion tree will eventually consider ALL valid matches. This can be
* useful when the user specifies a header like:
*
* "Copyright YEAR NAME - License"
*
* where "YEAR" and "NAME" are sections, meaning that we have to match a " "
* in-between, which can potentially match in multiple places if the actual
* values in the potential header contain spaces.
*
* @param potentialFileHeader
* the potential file header
* @param headerDefinition
* the header definition
* @param expectedTextBetweenSections
* the expected text between sections
* @param sectionsInOrder
* the sections interleaved with the expected text
* @param currentTextSegmentIndex
* the index of the current expected text segment to search for
* @param currentPotentialFileHeaderIndex
* the current search index into the potentialFileHeader
* @return true if a valid match is found
*/
private boolean recursivelyFindMatch(String potentialFileHeader, HeaderDefinition headerDefinition,
List<String> expectedTextBetweenSections, List<HeaderSection> sectionsInOrder, int currentTextSegmentIndex,
int currentPotentialFileHeaderIndex) {
if (currentTextSegmentIndex == expectedTextBetweenSections.size())
return true;
int currentSearchFromIndex = currentPotentialFileHeaderIndex;
while (true) {
String expectedText = expectedTextBetweenSections.get(currentTextSegmentIndex);
int index = potentialFileHeader.indexOf(expectedText, currentSearchFromIndex);
if (index == -1)
return false;
if (currentTextSegmentIndex > 0) {
HeaderSection section = sectionsInOrder.get(currentTextSegmentIndex - 1);
String sectionValue = potentialFileHeader.substring(currentPotentialFileHeaderIndex, index);
if (!ensureSectionMatch(headerDefinition, section, sectionValue))
return false;
}
if (recursivelyFindMatch(potentialFileHeader, headerDefinition, expectedTextBetweenSections,
sectionsInOrder, currentTextSegmentIndex + 1, index + expectedText.length()))
return true;
currentSearchFromIndex = index + 1;
}
}
/**
* If a header section has specified an "ensureMatch" value (see
* {@link HeaderSection#getEnsureMatch()}), then we verify that the contents
* of the section in the detected header do indeed match.
*
* @param headerDefinition
* the header definition for the current header match
* @param section
* the header section
* @param sectionValue
* the detected value of the section in the source file header
* @return false if the detected section value failed the match
*/
private boolean ensureSectionMatch(HeaderDefinition headerDefinition, HeaderSection section, String sectionValue) {
String match = section.getEnsureMatch();
if (!notEmpty(match))
return true;
String[] lines = sectionValue.split("\n");
/**
* We need to clean off any header-specific line-start characters before
* we perform the match
*/
String before = headerDefinition.getBeforeEachLine();
if (notEmpty(before)) {
for (int i = 0; i < lines.length; ++i) {
String line = lines[i];
if (line.startsWith(before))
lines[i] = line.substring(before.length());
}
}
/**
* If a multi-line match has been specified, we reconstruct the
* multi-line string (now sans line-start characters) and perform the
* match on the result
*/
if (section.isMultiLineMatch()) {
StringBuilder b = new StringBuilder();
for (int i = 0; i < lines.length; ++i) {
if (i > 0)
b.append('\n');
b.append(lines[i]);
}
String multiLineValue = b.toString();
return multiLineValue.matches(match);
}
for (String line : lines) {
if (!line.matches(match))
return false;
}
return true;
}
}