diff -r 7e08730da258 -r 4a1864c3e867 java/sql-dk/src/main/java/info/globalcode/sql/dk/batch/BatchDecoder.java --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/java/sql-dk/src/main/java/info/globalcode/sql/dk/batch/BatchDecoder.java Mon Mar 04 20:15:24 2019 +0100 @@ -0,0 +1,108 @@ +/** + * SQL-DK + * Copyright © 2014 František Kučera (frantovo.cz) + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ +package info.globalcode.sql.dk.batch; + +import info.globalcode.sql.dk.Parameter; +import info.globalcode.sql.dk.SQLCommand; +import info.globalcode.sql.dk.SQLCommandNumbered; +import java.io.DataInputStream; +import java.io.InputStream; +import static info.globalcode.sql.dk.batch.BatchConstants.*; +import static info.globalcode.sql.dk.Functions.toHex; +import info.globalcode.sql.dk.SQLType; +import java.io.IOException; +import java.util.ArrayList; +import java.util.Arrays; +import java.util.List; + +/** + * + * @author Ing. František Kučera (frantovo.cz) + */ +public class BatchDecoder { + + public Batch decode(InputStream in) throws BatchException { + return new BatchFromStream(new DataInputStream(in)); + } + + private class BatchFromStream implements Batch { + + private DataInputStream in; + private boolean hasNext; + + public BatchFromStream(DataInputStream in) throws BatchException { + this.in = in; + hasNext = verifyHeader(); + } + + @Override + public boolean hasNext() throws BatchException { + return hasNext; + } + + @Override + public SQLCommand next() throws BatchException { + try { + String sql = readNextString(); + + int paramCount = in.readInt(); + List parameters = new ArrayList<>(paramCount); + + for (int i = 0; i < paramCount; i++) { + SQLType type = SQLType.valueOf(in.readInt()); + String value = readNextString(); + parameters.add(new Parameter(value, type)); + } + + hasNext = verifyHeader(); + + SQLCommand sqlCommand = new SQLCommandNumbered(sql, parameters); + return sqlCommand; + } catch (IOException e) { + throw new BatchException("Unable to read batch", e); + } + } + + private String readNextString() throws IOException { + byte[] buffer = new byte[in.readInt()]; + in.read(buffer); + return new String(buffer, CHARSET); + } + + /** + * @return true if correct batch header was found | false if EOF was found + * @throws BatchException if unexpected data was found (not batch header nor EOF) + */ + private boolean verifyHeader() throws BatchException { + try { + byte[] buffer = new byte[BATCH_HEADER.length]; + int bytesRead = in.read(buffer); + + if (bytesRead == BATCH_HEADER.length && Arrays.equals(buffer, BATCH_HEADER)) { + return true; + } else if (bytesRead == -1) { + return false; + } else { + throw new BatchException("This is not SQL-DK batch: " + toHex(buffer)); + } + } catch (IOException e) { + throw new BatchException("Unable to read batch header", e); + } + } + } +}