FOP-3281: upgrade the maven checkstyle plugin from 2.14 to 3.6.0

Author: matthias8283

fop-core/src/main/codegen/fonts/font-file.xsl

@@ -52,10 +52,8 @@
 package org.apache.fop.fonts.base14;
 
 import java.awt.Rectangle;
-import java.net.URI;
-<xsl:if test="count(kerning) &gt; 0">
-import java.util.Map;
-</xsl:if>
+import java.net.URI;<xsl:if test="count(kerning) &gt; 0">
+import java.util.Map;</xsl:if>
 import java.util.Set;
 
 import org.apache.fop.fonts.Base14Font;

fop-core/src/main/java/org/apache/fop/afp/goca/GraphicsSetPatternSymbol.java

@@ -107,7 +107,7 @@ public void writeToStream(OutputStream os) throws IOException {
     /** {@inheritDoc} */
     public String toString() {
         return "GraphicsSetPatternSymbol(fill="
-            + (pattern == SOLID_FILL ? true : false)  + ")";
+            + (pattern == SOLID_FILL)  + ")";
     }
 
     /** {@inheritDoc} */

fop-core/src/main/java/org/apache/fop/afp/ptoca/TransparentDataControlSequence.java

@@ -28,7 +28,6 @@
 
 import org.apache.fop.afp.fonts.CharactersetEncoder.EncodedChars;
 import org.apache.fop.afp.ptoca.TransparentDataControlSequence.TransparentData;
-
 import static org.apache.fop.afp.ptoca.PtocaConstants.TRANSPARENT_DATA_MAX_SIZE;
 
 /**

fop-core/src/main/java/org/apache/fop/area/AreaTreeParser.java

@@ -91,7 +91,6 @@
 import org.apache.fop.util.XMLConstants;
 import org.apache.fop.util.XMLUtil;
 import org.apache.fop.utils.DefaultErrorListener;
-
 import static org.apache.fop.fo.Constants.FO_REGION_AFTER;
 import static org.apache.fop.fo.Constants.FO_REGION_BEFORE;
 import static org.apache.fop.fo.Constants.FO_REGION_BODY;

fop-core/src/main/java/org/apache/fop/area/CTM.java

@@ -26,7 +26,6 @@
 
 import org.apache.fop.datatypes.FODimension;
 import org.apache.fop.traits.WritingMode;
-
 import static org.apache.fop.fo.Constants.EN_LR_TB;
 import static org.apache.fop.fo.Constants.EN_RL_TB;
 import static org.apache.fop.fo.Constants.EN_TB_LR;

fop-core/src/main/java/org/apache/fop/area/LineArea.java

@@ -24,7 +24,6 @@
 import java.util.List;
 
 import org.apache.fop.area.inline.InlineArea;
-
 import static org.apache.fop.fo.Constants.EN_CENTER;
 import static org.apache.fop.fo.Constants.EN_END;
 import static org.apache.fop.fo.Constants.EN_JUSTIFY;

fop-core/src/main/java/org/apache/fop/area/Page.java

@@ -34,7 +34,6 @@
 import org.apache.fop.fo.properties.CommonMarginBlock;
 import org.apache.fop.layoutmgr.TraitSetter;
 import org.apache.fop.traits.WritingModeTraitsGetter;
-
 import static org.apache.fop.fo.Constants.EN_ERROR_IF_OVERFLOW;
 import static org.apache.fop.fo.Constants.EN_HIDDEN;
 import static org.apache.fop.fo.Constants.FO_REGION_AFTER;

fop-core/src/main/java/org/apache/fop/area/PageViewport.java

@@ -38,7 +38,6 @@
 import org.apache.fop.fo.flow.Markers;
 import org.apache.fop.fo.pagination.SimplePageMaster;
 import org.apache.fop.traits.WritingModeTraitsGetter;
-
 import static org.apache.fop.fo.Constants.FO_REGION_BODY;
 
 /**

fop-core/src/main/java/org/apache/fop/area/Trait.java

@@ -30,7 +30,6 @@
 import org.apache.fop.traits.Visibility;
 import org.apache.fop.traits.WritingMode;
 import org.apache.fop.util.ColorUtil;
-
 import static org.apache.fop.fo.Constants.EN_NOREPEAT;
 import static org.apache.fop.fo.Constants.EN_REPEAT;
 import static org.apache.fop.fo.Constants.EN_REPEATX;

fop-core/src/main/java/org/apache/fop/complexscripts/bidi/DelimitedTextRange.java

@@ -34,6 +34,7 @@
 import org.apache.fop.util.CharUtilities;
 
 // CSOFF: LineLengthCheck
+// CSOFF: InnerAssignment
 
 /**
  * The <code>DelimitedTextRange</code> class implements the "delimited text range" as described