Use StandardJarScanFilter.setTldSkip on Tomcat 8

Update SkipPatternJarScanner to apply skipped JARs to Tomcat 8's
StandardJarScanFilter.

Fixes gh-1686

spring-boot/src/main/java/org/springframework/boot/context/embedded/tomcat/SkipPatternJarScanner.java

@@ -16,6 +16,8 @@
 
 package org.springframework.boot.context.embedded.tomcat;
 
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
 import java.util.Collections;
 import java.util.LinkedHashSet;
 import java.util.Set;
@@ -27,6 +29,9 @@ import org.apache.tomcat.JarScanner;
 import org.apache.tomcat.JarScannerCallback;
 import org.apache.tomcat.util.scan.StandardJarScanner;
 import org.springframework.util.Assert;
+import org.springframework.util.ClassUtils;
+import org.springframework.util.ReflectionUtils;
+import org.springframework.util.StringUtils;
 
 /**
  * {@link JarScanner} decorator allowing alternative default jar pattern matching. This
@@ -38,6 +43,10 @@ import org.springframework.util.Assert;
  */
 class SkipPatternJarScanner extends StandardJarScanner {
 
+	private static final String JAR_SCAN_FILTER_CLASS = "org.apache.tomcat.JarScanFilter";
+
+	private static final String STANDARD_JAR_SCAN_FILTER_CLASS = "org.apache.tomcat.util.scan.StandardJarScanFilter";
+
 	private final JarScanner jarScanner;
 
 	private final SkipPattern pattern;
@@ -46,6 +55,32 @@ class SkipPatternJarScanner extends StandardJarScanner {
 		Assert.notNull(jarScanner, "JarScanner must not be null");
 		this.jarScanner = jarScanner;
 		this.pattern = (pattern == null ? new SkipPattern() : new SkipPattern(pattern));
+		setPatternToTomcat8SkipFilter(this.pattern);
+	}
+
+	private void setPatternToTomcat8SkipFilter(SkipPattern pattern) {
+		if (ClassUtils.isPresent(JAR_SCAN_FILTER_CLASS, null)) {
+			try {
+				Class<?> filterClass = Class.forName(JAR_SCAN_FILTER_CLASS);
+				Method setJarScanner = ReflectionUtils.findMethod(
+						StandardJarScanner.class, "setJarScanFilter", filterClass);
+				setJarScanner.invoke(this, createStandardJarScanFilter(pattern));
+			}
+			catch (Exception ex) {
+				throw new IllegalStateException(ex);
+			}
+		}
+	}
+
+	private Object createStandardJarScanFilter(SkipPattern pattern)
+			throws ClassNotFoundException, InstantiationException,
+			IllegalAccessException, InvocationTargetException {
+		Class<?> filterClass = Class.forName(STANDARD_JAR_SCAN_FILTER_CLASS);
+		Method setTldSkipMethod = ReflectionUtils.findMethod(filterClass, "setTldSkip",
+				String.class);
+		Object scanner = filterClass.newInstance();
+		setTldSkipMethod.invoke(scanner, pattern.asCommaDelimitedString());
+		return scanner;
 	}
 
 	@Override
@@ -124,6 +159,10 @@ class SkipPatternJarScanner extends StandardJarScanner {
 			this.patterns.add(patterns);
 		}
 
+		public String asCommaDelimitedString() {
+			return StringUtils.collectionToCommaDelimitedString(this.patterns);
+		}
+
 		public Set<String> asSet() {
 			return Collections.unmodifiableSet(this.patterns);
 		}