Allow SpringHeaderCheck to load custom files

Update `SpringHeaderCheck` to allow customer header files to be used.

Closes gh-70

Author: philwebb

spring-javaformat/spring-javaformat-checkstyle/src/main/java/io/spring/javaformat/checkstyle/SpringChecks.java

@@ -59,6 +59,8 @@ public class SpringChecks extends AbstractFileSetCheck implements ExternalResour
 
 	private String headerCopyrightPattern = SpringHeaderCheck.DEFAULT_HEADER_COPYRIGHT_PATTERN;
 
+	private String headerFile;
+
 	/**
 	 * Sets tab width.
 	 * @param tabWidth the distance between tab stops
@@ -91,12 +93,19 @@ public void finishLocalSetup() {
 		context.add("tabWidth", String.valueOf(this.tabWidth));
 		context.add("moduleFactory", this.moduleFactory);
 		Properties properties = new Properties();
-		properties.put("headerType", this.headerType);
-		properties.put("headerCopyrightPattern", this.headerCopyrightPattern);
+		put(properties, "headerType", this.headerType);
+		put(properties, "headerCopyrightPattern", this.headerCopyrightPattern);
+		put(properties, "headerFile", this.headerFile);
 		this.checks = new SpringConfigurationLoader(context, this.moduleFactory)
 				.load(new PropertiesExpander(properties));
 	}
 
+	private void put(Properties properties, String name, Object value) {
+		if (value != null) {
+			properties.put(name, value);
+		}
+	}
+
 	@Override
 	public Set<String> getExternalResourceLocations() {
 		Set<String> locations = new LinkedHashSet<>();
@@ -147,4 +156,8 @@ public void setHeaderCopyrightPattern(String headerCopyrightPattern) {
 		this.headerCopyrightPattern = headerCopyrightPattern;
 	}
 
+	public void setHeaderFile(String headerFile) {
+		this.headerFile = headerFile;
+	}
+
 }

spring-javaformat/spring-javaformat-checkstyle/src/main/java/io/spring/javaformat/checkstyle/check/SpringHeaderCheck.java

@@ -23,6 +23,10 @@
 import java.io.InputStreamReader;
 import java.io.LineNumberReader;
 import java.io.Reader;
+import java.io.UnsupportedEncodingException;
+import java.net.URI;
+import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.regex.Pattern;
@@ -59,36 +63,50 @@ public class SpringHeaderCheck extends AbstractFileSetCheck {
 	 */
 	public static final String DEFAULT_HEADER_COPYRIGHT_PATTERN = "20\\d\\d(-20\\d\\d)?";
 
+	private static final String DEFAULT_CHARSET = System.getProperty("file.encoding",
+			StandardCharsets.UTF_8.name());
+
+	private String charset = DEFAULT_CHARSET;
+
 	private String headerType = DEFAULT_HEADER_TYPE;
 
+	private URI headerFile;
+
 	private String headerCopyrightPattern = DEFAULT_HEADER_COPYRIGHT_PATTERN;
 
 	private String packageInfoHeaderType;
 
+	private URI packageInfoHeaderFile;
+
 	private HeaderCheck check;
 
 	private HeaderCheck packageInfoCheck;
 
 	@Override
 	protected void finishLocalSetup() throws CheckstyleException {
 		try {
-			this.check = createCheck(this.headerType);
-			this.packageInfoCheck = createCheck(this.packageInfoHeaderType != null
-					? this.packageInfoHeaderType : this.headerType);
+			this.check = createCheck(this.headerType, this.headerFile);
+			String packageInfoHeaderType = this.packageInfoHeaderType != null
+					? this.packageInfoHeaderType : this.headerType;
+			URI packageInfoHeaderFile = this.packageInfoHeaderFile != null
+					? this.packageInfoHeaderFile : this.headerFile;
+			this.packageInfoCheck = createCheck(packageInfoHeaderType,
+					packageInfoHeaderFile);
 		}
 		catch (IOException ex) {
 			throw new IllegalStateException(ex);
 		}
 	}
 
-	private HeaderCheck createCheck(String headerType) throws IOException {
+	private HeaderCheck createCheck(String headerType, URI headerFile)
+			throws IOException {
 		if (UNCHECKED.equals(headerType)) {
 			return HeaderCheck.NONE;
 		}
 		if (NONE.equals(headerType)) {
 			return new NoHeaderCheck();
 		}
-		return new RegexHeaderCheck(headerType, this.headerCopyrightPattern);
+		return new RegexHeaderCheck(headerType, headerFile);
 	}
 
 	@Override
@@ -104,10 +122,22 @@ private HeaderCheck getCheck(File file) {
 		return this.check;
 	}
 
+	public void setCharset(String charset) throws UnsupportedEncodingException {
+		if (!Charset.isSupported(charset)) {
+			throw new UnsupportedEncodingException(
+					"unsupported charset: '" + charset + "'");
+		}
+		this.charset = charset;
+	}
+
 	public void setHeaderType(String headerType) {
 		this.headerType = headerType;
 	}
 
+	public void setHeaderFile(URI headerFile) throws CheckstyleException {
+		this.headerFile = headerFile;
+	}
+
 	public void setHeaderCopyrightPattern(String headerCopyrightPattern) {
 		this.headerCopyrightPattern = headerCopyrightPattern;
 	}
@@ -116,6 +146,10 @@ public void setPackageInfoHeaderType(String packageInfoHeaderType) {
 		this.packageInfoHeaderType = packageInfoHeaderType;
 	}
 
+	public void setPackageInfoHeaderFile(URI packageInfoHeaderFile) {
+		this.packageInfoHeaderFile = packageInfoHeaderFile;
+	}
+
 	/**
 	 * Interface used to check for a header.
 	 */
@@ -142,27 +176,35 @@ private class RegexHeaderCheck implements HeaderCheck {
 
 		private final List<Pattern> lines;
 
-		RegexHeaderCheck(String type, String copyrightPattern) throws IOException {
+		RegexHeaderCheck(String type, URI file) throws IOException {
+			this.lines = loadLines(openInputStream(type, file));
+		}
+
+		private InputStream openInputStream(String type, URI file) throws IOException {
+			if (file != null) {
+				return file.toURL().openStream();
+			}
 			String name = "header-" + type + ".txt";
 			InputStream inputStream = SpringHeaderCheck.class.getResourceAsStream(name);
 			if (inputStream == null) {
 				throw new IllegalStateException("Unknown header type " + type);
 			}
-			this.lines = loadLines(inputStream, copyrightPattern);
+			return inputStream;
 		}
 
-		private List<Pattern> loadLines(InputStream inputStream, String copyrightPattern)
-				throws IOException {
+		private List<Pattern> loadLines(InputStream inputStream) throws IOException {
 			inputStream = new BufferedInputStream(inputStream);
-			try (Reader reader = new InputStreamReader(inputStream, "UTF-8")) {
+			try (Reader reader = new InputStreamReader(inputStream,
+					SpringHeaderCheck.this.charset)) {
 				LineNumberReader lineReader = new LineNumberReader(reader);
 				List<Pattern> lines = new ArrayList<>();
 				while (true) {
 					String line = lineReader.readLine();
 					if (line == null) {
 						return lines;
 					}
-					lines.add(loadLine(line, copyrightPattern));
+					lines.add(loadLine(line,
+							SpringHeaderCheck.this.headerCopyrightPattern));
 				}
 			}
 		}

spring-javaformat/spring-javaformat-checkstyle/src/main/resources/io/spring/javaformat/checkstyle/spring-checkstyle.xml

@@ -8,6 +8,7 @@
 	<module name="io.spring.javaformat.checkstyle.check.SpringHeaderCheck">
 		<property name="fileExtensions" value="java" />
 		<property name="headerType" value="${headerType}"/>
+		<property name="headerFile" value="${headerFile}" default=""/>
 		<property name="headerCopyrightPattern" value="${headerCopyrightPattern}"/>
 	</module>
 	<module name="com.puppycrawl.tools.checkstyle.checks.NewlineAtEndOfFileCheck">

spring-javaformat/spring-javaformat-checkstyle/src/test/java/io/spring/javaformat/checkstyle/SpringConfigurationLoaderTests.java

@@ -52,6 +52,7 @@ public void loadShouldLoadChecks() {
 	private PropertyResolver getPropertyResolver() {
 		Properties properties = new Properties();
 		properties.put("headerType", SpringHeaderCheck.DEFAULT_HEADER_TYPE);
+		properties.put("headerFile", "");
 		properties.put("headerCopyrightPattern",
 				SpringHeaderCheck.DEFAULT_HEADER_COPYRIGHT_PATTERN);
 		return new PropertiesExpander(properties);

spring-javaformat/spring-javaformat-checkstyle/src/test/resources/check/HeaderFile.txt

@@ -0,0 +1 @@
++0 errors

spring-javaformat/spring-javaformat-checkstyle/src/test/resources/config/HeaderFile.xml

@@ -0,0 +1,9 @@
+<?xml version="1.0"?>
+<!DOCTYPE module PUBLIC
+		"-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
+		"https://checkstyle.org/dtds/configuration_1_3.dtd">
+<module name="com.puppycrawl.tools.checkstyle.Checker">
+	<module name="io.spring.javaformat.checkstyle.SpringChecks">
+		<property name="headerFile" value="src/test/resources/customHeaderFile.txt"/>
+	</module>
+</module>

spring-javaformat/spring-javaformat-checkstyle/src/test/resources/customHeaderFile.txt

@@ -0,0 +1 @@
+// (c) Somebody ${copyright-pattern}

spring-javaformat/spring-javaformat-checkstyle/src/test/resources/source/HeaderFile.java

@@ -0,0 +1,10 @@
+// (c) Somebody 2017-2019
+
+/**
+ * A custom header file.
+ *
+ * @author Phillip Webb
+ */
+public class HeaderFile {
+
+}