Encoder 由接象类改为接口

src/main/java/com/jfinal/template/io/Encoder.java

@@ -19,10 +19,10 @@ package com.jfinal.template.io;
 /**
  * Encoder
  */
-public abstract class Encoder {
+public interface Encoder {
 	
-	public abstract float maxBytesPerChar();
+	public float maxBytesPerChar();
 	
-	public abstract int encode(char[] chars, int offset, int len, byte[] bytes);
+	public int encode(char[] chars, int offset, int len, byte[] bytes);
 }
 

src/main/java/com/jfinal/template/io/JdkEncoder.java

@@ -26,7 +26,7 @@ import java.nio.charset.CoderResult;
 /**
  * JdkEncoder
  */
-public class JdkEncoder extends Encoder {
+public class JdkEncoder implements Encoder {
 	
 	private CharsetEncoder ce;
 	

src/main/java/com/jfinal/template/io/Utf8Encoder.java

@@ -24,7 +24,7 @@ package com.jfinal.template.io;
  * http://grepcode.com/file/repository.grepcode.com/java/root/jdk/openjdk/8u40-b25/sun/nio/cs/UTF_8.java?av=f
  * http://grepcode.com/search?query=ArrayEncoder&start=0&entity=type&n=
  */
-public class Utf8Encoder extends Encoder {
+public class Utf8Encoder implements Encoder {
 	
 	public static final Utf8Encoder me = new Utf8Encoder();