Back to project page RadaeePDF-B4A.
The source code is released under:
Apache License
If you think the Android project RadaeePDF-B4A listed in this page is inappropriate, such as containing malicious code/tools or violating the copyright, please email info at java2s dot com, thanks.
package com.radaee.util; //from w ww.j a v a 2 s . c om import java.io.File; import java.io.InputStream; import java.io.RandomAccessFile; import java.net.HttpURLConnection; import java.net.URL; import android.os.Handler; import android.os.Looper; import android.os.Message; import android.util.Log; import com.radaee.pdf.Document.PDFStream; /** * a class for HttpURLConnection.<br/> * the class read PDF file in remote way, this class not support write back to server.<br/> * the server must support Http header "Range" for request, and "content-length" for response.<br/> * and this class need Internet access right to run. * @author radaee */ public class PDFHttpStream implements PDFStream { private static final int BLOCK_SIZE = 8192; private String m_url = null; private File m_tmp = null; private int m_total = 0; private RandomAccessFile m_cache = null; private HttpThread m_thread = null; private int m_block_pos = 0; private byte[] m_block = null; private int m_pos = 0; private int[] m_blocks_flag = null; /** Inner class.<br/> developer should not use this. */ public class HttpThread extends Thread { private Handler m_hand = null; private boolean is_notified = false; private boolean is_waitting = false; private class OP { PDFHttpStream stream; int para1; int para2; byte[] data; } private synchronized void wait_op() { try { if( is_notified ) is_notified = false; else { is_waitting = true; wait(); is_waitting = false; } } catch(Exception e) { } } private synchronized void notify_op() { if( is_waitting ) notify(); else is_notified = true; } @Override public void start() { super.start(); wait_op(); } @Override public void run() { Looper.prepare(); m_hand = new Handler(Looper.myLooper()) { public void handleMessage(Message msg) { if( msg != null ) { if( msg.what == 0 )//render function { OP op = (OP)msg.obj; op.para1 = op.stream.read_total_size(); notify_op(); super.handleMessage(msg); } else if( msg.what == 1 ) { OP op = (OP)msg.obj; op.data = op.stream.read_range(op.para1, op.para2); notify_op(); super.handleMessage(msg); } else if( msg.what == 100 )//quit { super.handleMessage(msg); getLooper().quit(); } else { super.handleMessage(msg); } } else getLooper().quit(); } }; notify_op(); Looper.loop(); } public int get_size(PDFHttpStream stream) { OP op = new OP(); op.stream = stream; m_hand.sendMessage(m_hand.obtainMessage(0, op)); wait_op(); return op.para1; } public byte[] read_range(PDFHttpStream stream, int start, int len) { OP op = new OP(); op.stream = stream; op.para1 = start; op.para2 = len; m_hand.sendMessage(m_hand.obtainMessage(1, op)); wait_op(); return op.data; } public synchronized void destroy() { try { m_hand.sendEmptyMessage(100); join(); m_hand = null; } catch(InterruptedException e) { } } } /** * this method need http_header "content-length" for server. * @return total size of PDF */ private int read_total_size() { try { URL url = new URL(m_url); HttpURLConnection conn = (HttpURLConnection)url.openConnection(); conn.setRequestMethod("GET"); conn.setRequestProperty("Connection", "Keep-Alive"); conn.connect(); int len = 0; try { len = conn.getContentLength(); } catch(Exception e) { len = 0; } if( len <= 0 ) { try { String slen = conn.getHeaderField("Content-Length"); len = Integer.parseInt(slen); } catch(Exception e) { len = 0; } } //it's better to comment this line in release version. Log.d("Total Size:", String.valueOf(len) ); conn.disconnect(); return len; } catch(Exception e) { Log.d("Error", e.getMessage()); return (int) 0; } } private byte[] read_range( int start, int len ) { try { long time1 = System.currentTimeMillis(); URL url = new URL(m_url); HttpURLConnection conn = (HttpURLConnection)url.openConnection(); conn.setRequestMethod("GET"); conn.setRequestProperty("Range", String.format("bytes=%d-%d", start, start + len)); conn.setRequestProperty("Connection", "Keep-Alive"); conn.connect(); InputStream stream = conn.getInputStream(); byte[] data = new byte[len]; int read = 0; int read_total = 0; while( read_total < len ) { read = stream.read(data, read_total, len - read_total); if( read > 0 ) read_total += read; } stream.close(); conn.disconnect(); long time2 = System.currentTimeMillis(); //it's better to comment this line in release version. Log.d(String.format("Time:%06d %d", start/BLOCK_SIZE, len), String.valueOf(time2 - time1)); return data; } catch(Exception e) { Log.d("Error", e.getMessage()); return null; } } private byte[] read_block(int index) { try { m_cache.seek(index * BLOCK_SIZE); int size = BLOCK_SIZE; if( index == m_blocks_flag.length - 1 ) size = m_total%BLOCK_SIZE; byte[] data; if( m_blocks_flag[index] != 0 ) { data = new byte[size]; m_cache.read(data); return data; } else { data = m_thread.read_range(this, index * BLOCK_SIZE, size); if( data != null ) { m_cache.write(data); m_blocks_flag[index] = 1; } return data; } } catch(Exception e) { Log.d("Error", e.getMessage()); return null; } } /** * open an url as stream * @param url url address. * @return true or false. */ public boolean open(String url) { m_url = url; m_thread = new HttpThread(); m_thread.start(); try { m_total = m_thread.get_size(this); if( m_total <= 0 ) return false; m_tmp = File.createTempFile("RDTMP", ".dat"); m_cache = new RandomAccessFile(m_tmp.getAbsolutePath(), "rw"); m_cache.setLength(m_total); m_blocks_flag = new int[(m_total + BLOCK_SIZE - 1)/BLOCK_SIZE]; m_block = read_block(0); return true; } catch(Exception e) { Log.d("Error", e.getMessage()); return false; } } /** * free resources.<br/> * this method is needed when APP close the PDF. */ public void close() { try { m_thread.destroy(); m_cache.close(); m_tmp.delete(); } catch(Exception e) { } } public boolean writeable() { return false; } public int get_size() { return m_total; } public int read(byte[] data) { int dst_cur = 0; int old_pos = m_pos; while( dst_cur < data.length && m_pos < m_total ) { if( dst_cur > 0 ) { seek( old_pos + dst_cur ); } int src_cur = m_pos%BLOCK_SIZE; while( dst_cur < data.length && src_cur < m_block.length ) { data[dst_cur] = m_block[src_cur]; dst_cur++; src_cur++; } seek( old_pos + dst_cur ); } return dst_cur; } public int write(byte[] data) { return 0; } public void seek(int pos) { if( pos < 0 ) pos = 0; if( pos > m_total ) pos = m_total; if( pos == m_pos ) return; m_pos = pos; int new_block_pos = pos/BLOCK_SIZE; if( new_block_pos == m_block_pos ) return; m_block_pos = new_block_pos; m_block = read_block(m_block_pos); } public int tell() { return m_pos; } }