HeaderSource.java
/*
* Copyright (C) 2008-2022 Mycila (mathieu.carbou@gmail.com)
*
* 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
*
* https://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.mycila.maven.plugin.license.header;
import com.mycila.maven.plugin.license.Multi;
import com.mycila.maven.plugin.license.util.FileUtils;
import com.mycila.maven.plugin.license.util.resource.ResourceFinder;
import org.apache.maven.plugin.MojoFailureException;
import java.io.IOException;
import java.net.URL;
import static com.mycila.maven.plugin.license.Multi.DEFAULT_SEPARATOR;
/**
* Provides an access to the license template text.
*
* @author <a href="https://github.com/ppalaga">Peter Palaga</a>
*/
public abstract class HeaderSource {
/**
* A {@link HeaderSource} built from a license header template literal.
*/
public static class LiteralHeaderSource extends HeaderSource {
public LiteralHeaderSource(String content) {
super(content, true);
}
/**
* @return always {@code false} because this {@link LiteralHeaderSource} was not loaded from any {@link URL}
*/
@Override
public boolean isFromUrl(URL location) {
return false;
}
@Override
public String toString() {
return "inline: " + content;
}
}
/**
* A {@link HeaderSource} loaded from a {@link URL}.
*/
public static class UrlHeaderSource extends HeaderSource {
private final URL url;
public UrlHeaderSource(URL url, String encoding) throws IOException {
super(FileUtils.read(url, encoding), false);
this.url = url;
}
@Override
public boolean isFromUrl(URL location) {
return this.url.equals(location);
}
@Override
public String toString() {
return url + ": " + content;
}
}
/**
* A {@link HeaderSource} built from multiple license header template literals.
*/
public static class MultiLiteralHeaderSource extends HeaderSource {
public MultiLiteralHeaderSource(final String preamble, final String[] contents, final String[] separators) {
super(combineHeaders(preamble, contents, separators), true);
}
/**
* @return always {@code false} because this {@link LiteralHeaderSource} was not loaded from any {@link URL}
*/
@Override
public boolean isFromUrl(final URL location) {
return false;
}
@Override
public String toString() {
return "inline: " + content;
}
}
/**
* A {@link HeaderSource} loaded from multiple {@link URL}.
*/
public static class MultiUrlHeaderSource extends HeaderSource {
private final URL[] urls;
public MultiUrlHeaderSource(final String preamble, final URL[] urls, final String[] separators, final String encoding) throws IOException {
super(combineHeaders(preamble, FileUtils.read(urls, encoding), separators), false);
this.urls = urls;
}
@Override
public boolean isFromUrl(final URL location) {
for (final URL url : urls) {
if (url.equals(location)) {
return true;
}
}
return false;
}
@Override
public String toString() {
final StringBuilder builder = new StringBuilder();
builder.append('[');
for (final URL url : urls) {
if (builder.length() > 1) {
builder.append(", ");
}
builder.append(url);
}
builder.append("] : ").append(content);
return builder.toString();
}
}
private static String combineHeaders(final String preamble, final String[] headers, final String[] separators) {
final StringBuilder builder = new StringBuilder();
// preamble
if (preamble != null) {
builder.append(preamble);
if (!preamble.endsWith("\n")) {
builder.append('\n');
}
builder.append('\n');
}
for (int i = 0; i < headers.length; i++) {
// separator
String separator = null;
if (i > 0) {
if (separators == null) {
separator = DEFAULT_SEPARATOR;
} else if (separators.length == 1) {
separator = separators[0];
} else {
separator = separators[i - 1];
}
if (builder.charAt(builder.length() - 1) != '\n') {
builder.append('\n');
}
builder.append('\n');
builder.append(separator);
if (!separator.endsWith("\n")) {
builder.append('\n');
}
builder.append('\n');
}
// header
final String header = headers[i];
builder.append(header);
}
return builder.toString();
}
public static HeaderSource of(String headerPath, String encoding, ResourceFinder finder) {
return of(null, encoding, finder);
}
/**
* Checking the params left to right, returns the first available {@link HeaderSource} that can be created. If
* {@code inlineHeader} is not {@code null} returns a new {@link LiteralHeaderSource}. Otherwise attempts to create a
* new {@link UrlHeaderSource} out of {@code headerPath} and {@code encoding}.
*
* @param multi container for multi license, or null if single license
* @param inlineHeader the text of a license header template
* @param headerPath a path resolvable by the {@code finder}
* @param encoding the encoding to use when reading {@code headerPath}
* @param finder the {@link ResourceFinder} to use to resolve {@code headerPath}
* @return a new {@link HeaderSource}
*/
public static HeaderSource of(Multi multi, String inlineHeader, String headerPath, String encoding, ResourceFinder finder) {
if (multi != null) {
if (multi.getInlineHeaders() != null && multi.getInlineHeaders().length > 0) {
return new MultiLiteralHeaderSource(multi.getPreamble(), multi.getInlineHeaders(), multi.getSeparators());
} else if (multi.getHeaders() == null || multi.getHeaders().length == 0) {
throw new IllegalArgumentException("Either multi/inlineHeader or multi/header path needs to be specified");
} else {
final URL[] headerUrls = new URL[multi.getHeaders().length];
for (int i = 0; i < multi.getHeaders().length; i++) {
try {
headerPath = multi.getHeaders()[i];
final URL headerUrl = finder.findResource(headerPath);
headerUrls[i] = headerUrl;
} catch (final MojoFailureException e) {
throw new IllegalArgumentException(
"Cannot read header document " + headerPath + ". Cause: " + e.getMessage(), e);
}
}
try {
return new MultiUrlHeaderSource(multi.getPreamble(), headerUrls, multi.getSeparators(), encoding);
} catch (final IOException e) {
throw new IllegalArgumentException(
"Cannot read multi header documents. Cause: " + e.getMessage(), e);
}
}
} else {
if (inlineHeader != null && !inlineHeader.isEmpty()) {
return new LiteralHeaderSource(inlineHeader);
} else if (headerPath == null) {
throw new IllegalArgumentException("Either inlineHeader or header path needs to be specified");
} else {
try {
final URL headerUrl = finder.findResource(headerPath);
return new UrlHeaderSource(headerUrl, encoding);
} catch (Exception e) {
throw new IllegalArgumentException(
"Cannot read header document " + headerPath + ". Cause: " + e.getMessage(), e);
}
}
}
}
protected final String content;
private final boolean inline;
protected HeaderSource(String content, boolean inline) {
super();
this.content = content;
this.inline = inline;
}
/**
* @return the text of the license template
*/
public String getContent() {
return content;
}
/**
* @return {@code true} if this {@link HeaderSource} was created from a string rather by loading the bits from an
* URL; {@code false} otherwise
*/
public boolean isInline() {
return inline;
}
/**
* Retuns {@code true} if this {@link HeaderSource} was loaded from the URL given in the {@code location} parameter
* or {@code false} otherwise.
*
* @param location the URL to tell if this {@link HeaderSource} was loaded from it
* @return {@code true} if this {@link HeaderSource} was loaded from the URL given in the {@code location} parameter
* or {@code false} otherwise
*/
public abstract boolean isFromUrl(URL location);
}