From 6fddbff83356c71e3da002c5b6c9281ab33060c6 Mon Sep 17 00:00:00 2001 From: free will <2647778488@qq.com> Date: Sat, 6 Mar 2021 16:20:17 +0800 Subject: [PATCH] finished encoder --- src/main/java/encoding/Block.java | 8 +-- src/main/java/encoding/Encoder.java | 79 ++++++++++++++++++++++++++++- src/main/java/encoding/SizeT.java | 24 ++++++--- src/main/java/encoding/VlInt.java | 36 +++++++++++-- 4 files changed, 131 insertions(+), 16 deletions(-) diff --git a/src/main/java/encoding/Block.java b/src/main/java/encoding/Block.java index 0b796bd..e3fb196 100644 --- a/src/main/java/encoding/Block.java +++ b/src/main/java/encoding/Block.java @@ -50,14 +50,14 @@ public class Block { } // 读取length - VlInt tlvLength=TLV.readVarNumber(buffer,new VlInt(tlvType.SizeOfVarNumber())); + VlInt tlvLength=TLV.readVarNumber(buffer,new VlInt(tlvType.size())); if(tlvLength==null){ return null; } return createBlockByTypeLengthBuffer(tlvType,tlvLength, - ByteHelper.getLenBytes(buffer,new VlInt(tlvType.SizeOfVarNumber()+tlvLength.SizeOfVarNumber()), - buffer.length-(tlvType.SizeOfVarNumber()+tlvLength.SizeOfVarNumber())),verifyLength); + ByteHelper.getLenBytes(buffer,new VlInt(tlvType.size()+tlvLength.size()), + buffer.length-(tlvType.size()+tlvLength.size())),verifyLength); } /** @@ -130,7 +130,7 @@ public class Block { if(!this.isValid()){ return null; } - return new SizeT(this.tlvType.SizeOfVarNumber()+this.length.SizeOfVarNumber()+this.value.length); + return new SizeT(this.tlvType.size()+this.length.size()+this.value.length); } /** diff --git a/src/main/java/encoding/Encoder.java b/src/main/java/encoding/Encoder.java index 2562083..cda4c63 100644 --- a/src/main/java/encoding/Encoder.java +++ b/src/main/java/encoding/Encoder.java @@ -162,6 +162,83 @@ public class Encoder { return 0; } - + /** + * 在前向插入一个可变长度的数字 + * @param varNumber + * @return + */ + public int prependVarNumber(VlInt varNumber){ + return this.prependByteArray(varNumber.getVlIntBytes(),new SizeT(varNumber.size())); + } + /** + * 在后向插入一个可变长度的数字 + * @param varNumber + * @return + */ + public int appendVarNumber(VlInt varNumber){ + return this.appendByteArray(varNumber.getVlIntBytes(),new SizeT(varNumber.size())); + } + + //todo: 在前向&后向插入一个非负整数 + + /** + * 根据TLV-TYPE和一个字节数组，在前向插入一个 TLV Block + * @param tlvType + * @param array + * @param size + * @return + */ + public int prependByteArrayBlock(VlInt tlvType,byte[] array,SizeT size){ + int totalLength=this.prependByteArray(array,size); + totalLength+=this.prependVarNumber(new VlInt(size)); + totalLength+=this.prependVarNumber(tlvType); + return totalLength; + } + + /** + * 根据TLV-TYPE和一个字节数组，在后向插入一个 TLV Block + * @param tlvType + * @param array + * @param size + * @return + */ + public int appendByteArrayBlock(VlInt tlvType,byte[] array,SizeT size){ + int totalLength=this.appendByteArray(array,size); + totalLength+=this.appendVarNumber(new VlInt(size.getVlIntValue2Long())); + totalLength+=this.appendVarNumber(tlvType); + return totalLength; + } + + /** + * 在前向插入一个 TLV Block + * @param block + * @return + */ + public int prependBlock(Block block){ + return this.prependByteArrayBlock(block.getTlvType(),block.getValue(),new SizeT(block.getLength())); + } + + /** + * 在后向插入一个 TLV Block + * @param block + * @return + */ + public int appendBlock(Block block){ + return this.appendByteArrayBlock(block.getTlvType(),block.getValue(),new SizeT(block.getLength())); + } + + /** + * 获取编码后的字节数组 + * @return + */ + public byte[] getBuffer() { + if((!this.isInitial)||this.isEstimator){ + return null; + } + int len=this.right-this.left-1; + byte[] res=new byte[len]; + System.arraycopy(this.buffer,this.left+1,res,0,len); + return res; + } } diff --git a/src/main/java/encoding/SizeT.java b/src/main/java/encoding/SizeT.java index 9a20daf..264e345 100644 --- a/src/main/java/encoding/SizeT.java +++ b/src/main/java/encoding/SizeT.java @@ -7,7 +7,7 @@ import static java.lang.Math.pow; /* * @Author: Wang Feng * @Description:变长无符号整型，用于表示TLV中的T和L - * todo: 本类需要在VlInt经过彻底测试之后，再进行完善。或可直接继承vlint + * todo: 本类需要在VlInt经过彻底测试之后，再进行完善。或可直接继承vlint，或可内包装一个VlInt. * @Version: 1.0.0 * @Date: 18:13 2021/3/1 * @Copyright: MIN-Group；国家重大科技基础设施——未来网络北大实验室；深圳市信息论与未来网络重点实验室 @@ -17,13 +17,15 @@ public class SizeT { private byte[] VlIntBytes; // 变长整数表示的真实数值 private BigInteger VlIntValue; + // 变长整数的长度: 1 3 5 9 ... + private int size; /** * 测量一个变长整型实际用几个字节表示 * @return */ - public int SizeOfVarNumber(){ - return SizeOfVarNumber(this.VlIntValue); + public int size(){ + return this.size; } private static int SizeOfVarNumber(BigInteger bigInteger){ if(bigInteger.compareTo(BigInteger.valueOf(Long.parseLong("241"))) < 0){ @@ -48,6 +50,12 @@ public class SizeT { this.VlIntValue=vlintBytes2bigInteger(bytes); } + public SizeT(VlInt vlInt){ + this.VlIntBytes=vlInt.getVlIntBytes(); + this.VlIntValue=vlInt.getVlIntValue(); + this.size = vlInt.size(); + } + public SizeT(BigInteger bigInteger){ this.VlIntValue=bigInteger; this.VlIntBytes=bigInteger2vlintBytes(bigInteger); @@ -63,6 +71,10 @@ public class SizeT { return new SizeT(bigInteger); } + public byte[] getVlIntBytes(){ + return this.VlIntBytes; + } + // todo:传入一个int，将它解析成一个VlInt public SizeT(int i){ this.VlIntValue=new BigInteger(String.valueOf(i)); @@ -78,7 +90,7 @@ public class SizeT { // 将vlint转为一个int输出：需要判断size是不是小于4(1 or 3) public int getVlIntValue2Int(){ - if(this.SizeOfVarNumber()<4){ + if(this.size()<4){ return VlIntValue.intValue(); } return Integer.parseInt(null); @@ -86,7 +98,7 @@ public class SizeT { // 将vlint转为一个long输出：需要判断size是不是小于8(5) public long getVlIntValue2Long(){ - if(this.SizeOfVarNumber()<8){ + if(this.size()<8){ return VlIntValue.longValue(); } return Long.parseLong(null); @@ -94,7 +106,7 @@ public class SizeT { // 将vlint转为一个biginteger输出：需要判断size是不是等于9(9) public BigInteger getVlIntValue(){ - if(this.SizeOfVarNumber()>=9){ + if(this.size()>=9){ return VlIntValue; } return null; diff --git a/src/main/java/encoding/VlInt.java b/src/main/java/encoding/VlInt.java index 08851d4..72ee337 100644 --- a/src/main/java/encoding/VlInt.java +++ b/src/main/java/encoding/VlInt.java @@ -20,6 +20,8 @@ public class VlInt { private byte[] VlIntBytes; // 变长整数表示的真实数值 private BigInteger VlIntValue; + // 变长整数的长度: 1 3 5 9 ... + private int size; // 一些int常量 // @Description: @@ -32,12 +34,17 @@ public class VlInt { public static final int VlIntExtend4=242; public static final int VlIntExtend8=243; + public static final int VlIntSize1=1; + public static final int VlIntSize3=3; + public static final int VlIntSize5=5; + public static final int VlIntSize9=9; + /** * 测量一个变长整型实际用几个字节表示 * @return */ - public int SizeOfVarNumber(){ - return SizeOfVarNumber(this.VlIntValue); + public int size(){ + return this.size; } private static int SizeOfVarNumber(BigInteger bigInteger){ if(bigInteger.compareTo(BigInteger.valueOf(241)) < 0){ @@ -54,27 +61,42 @@ public class VlInt { } //todo:判断bytes是否是一个合法的变长非负整型 + private boolean isValidVlIntBytes(){ + return true; + } //todo:判断biginteger是否合法 public VlInt(byte[] bytes){ this.VlIntBytes=bytes; this.VlIntValue=vlintBytes2bigInteger(bytes); + if(this.VlIntValue != null) { + this.size = SizeOfVarNumber(this.VlIntValue); + } } public VlInt(BigInteger bigInteger){ this.VlIntValue=bigInteger; this.VlIntBytes=bigInteger2vlintBytes(bigInteger); + this.size=SizeOfVarNumber(this.VlIntValue); + } + + public VlInt(SizeT sizeT){ + this.VlIntBytes=sizeT.getVlIntBytes(); + this.VlIntValue=sizeT.getVlIntValue(); + this.size = sizeT.size(); } public VlInt(int i){ this.VlIntValue=BigInteger.valueOf(i); this.VlIntBytes=bigInteger2vlintBytes(this.VlIntValue); + this.size=SizeOfVarNumber(this.VlIntValue); } public VlInt(long l){ this.VlIntValue=BigInteger.valueOf(l); this.VlIntBytes=bigInteger2vlintBytes(this.VlIntValue); + this.size=SizeOfVarNumber(this.VlIntValue); } // 传入一个变长无符号字节数组byte[]，将它解析成一个VlInt @@ -87,12 +109,16 @@ public class VlInt { return new VlInt(bigInteger); } + public byte[] getVlIntBytes(){ + return this.VlIntBytes; + } + /** * 将vlint转为一个int输出：需要判断size是不是小于4(1 or 3) * @return */ public int getVlIntValue2Int(){ - if(this.SizeOfVarNumber()<4){ + if(this.size()<4){ return VlIntValue.intValue(); } return Integer.parseInt(null); @@ -103,7 +129,7 @@ public class VlInt { * @return */ public long getVlIntValue2Long(){ - if(this.SizeOfVarNumber()<8){ + if(this.size()<8){ return VlIntValue.longValue(); } return Long.parseLong(null); @@ -114,7 +140,7 @@ public class VlInt { * @return */ public BigInteger getVlIntValue(){ - if(this.SizeOfVarNumber()>=9){ + if(this.size()>=9){ return VlIntValue; } return null;