java/src/pursuer/pxprpc/Utils.java

   1 package pursuer.pxprpc;
   2
   3 import java.io.EOFException;
   4 import java.io.IOException;
   5 import java.nio.Buffer;
   6 import java.nio.ByteBuffer;
   7 import java.nio.ByteOrder;
   8 import java.nio.channels.ByteChannel;
   9
  10 public class Utils {
  11         // read enough data or EOFException
  12         public static void readf(ByteChannel in,ByteBuffer b) throws IOException {
  13                 //java9 method signature change, which may cause error when runing on lower java version(usually happen on android).
  14                 Buffer b2=b;
  15                 for(b2.mark();b2.remaining()>0 && in.isOpen();) {
  16                         if(in.read(b)<0) {
  17                                 throw new EOFException();
  18                         }
  19                 }
  20                 b2.reset();
  21         }
  22
  23         public static int readInt32(ByteChannel in) throws IOException {
  24                 ByteBuffer b = ByteBuffer.allocate(4);
  25                 readf(in,b);
  26                 return b.order(ByteOrder.LITTLE_ENDIAN).getInt();
  27         }
  28         public static long readInt64(ByteChannel in) throws IOException {
  29                 ByteBuffer b = ByteBuffer.allocate(8);
  30                 readf(in,b);
  31                 return b.order(ByteOrder.LITTLE_ENDIAN).getLong();
  32         }
  33         public static float readFloat32(ByteChannel in) throws IOException {
  34                 ByteBuffer b = ByteBuffer.allocate(4);
  35                 readf(in,b);
  36                 return b.order(ByteOrder.LITTLE_ENDIAN).getFloat();
  37         }
  38         public static double readFloat64(ByteChannel in) throws IOException {
  39                 ByteBuffer b = ByteBuffer.allocate(8);
  40                 readf(in,b);
  41                 return b.order(ByteOrder.LITTLE_ENDIAN).getDouble();
  42         }
  43
  44         public static void writef(ByteChannel out,ByteBuffer b) throws IOException {
  45                 Buffer b2=b;
  46                 for(b2.mark();
  47                                 b2.remaining()>0 && out.isOpen();
  48                                 out.write(b)) {}
  49                 b2.reset();
  50         }
  51         public static void writeInt32(ByteChannel out,int d) throws IOException {
  52                 ByteBuffer b=ByteBuffer.allocate(4).order(ByteOrder.LITTLE_ENDIAN).putInt(d);
  53                 ((Buffer)b).flip();
  54                 writef(out,b);
  55         }
  56         public static void writeInt64(ByteChannel out,long d) throws IOException {
  57                 ByteBuffer b=ByteBuffer.allocate(8).order(ByteOrder.LITTLE_ENDIAN).putLong(d);
  58                 ((Buffer)b).flip();
  59                 writef(out,b);
  60         }
  61         public static void writeFloat32(ByteChannel out,float d) throws IOException {
  62                 ByteBuffer b=ByteBuffer.allocate(4).order(ByteOrder.LITTLE_ENDIAN).putFloat(d);
  63                 ((Buffer)b).flip();
  64                 writef(out,b);
  65         }
  66         public static void writeFloat64(ByteChannel out,double d) throws IOException {
  67                 ByteBuffer b=ByteBuffer.allocate(8).order(ByteOrder.LITTLE_ENDIAN).putDouble(d);
  68                 ((Buffer)b).flip();
  69                 writef(out,b);
  70         }
  71         public static ByteBuffer setPos(ByteBuffer bb,int pos){
  72                 Buffer b=bb;
  73                 b.position(pos);
  74                 return bb;
  75         }
  76         public static int getPos(ByteBuffer bb){
  77                 Buffer b=bb;
  78                 return b.position();
  79         }
  80         public static byte[] toBytes(ByteBuffer bb){
  81                 byte[] b2=new byte[bb.remaining()];
  82                 bb.get(b2);
  83                 return b2;
  84         }
  85         public static ByteBuffer ensureBuffer(ByteBuffer bb,int remainSize){
  86                 Buffer b=bb;
  87                 int size=remainSize+b.position();
  88                 if(b.capacity()<size){
  89                         ByteBuffer newbuf=ByteBuffer.allocate(size+(size>>1));
  90                         newbuf.put(newbuf.array(),0,b.position());
  91                         return newbuf;
  92                 }
  93                 return bb;
  94         }
  95
  96         public static byte[] bytesGet(ByteBuffer bb,int off,int len) {
  97                 Buffer bb2=bb;
  98                 bb2.mark();
  99                 bb2.position(bb2.position()+off);
 100                 byte[] b = new byte[len];
 101                 bb.get(b);
 102                 bb2.reset();
 103                 return b;
 104         }
 105         public static void bytesSet(ByteBuffer bb,int off,int len,byte[] b) {
 106                 Buffer bb2=bb;
 107                 bb2.mark();
 108                 bb2.position(bb2.position()+off);
 109                 bb.put(b);
 110                 bb2.reset();
 111         }
 112         public static String stringJoin(String delim,Iterable<String> iter){
 113                 StringBuilder sb=new StringBuilder();
 114                 for(String e:iter) {
 115                         sb.append(e);
 116                         sb.append(delim);
 117                 }
 118                 return sb.substring(0,sb.length()-delim.length());
 119         }
 120 }