--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/java/sql-dk/src/info/globalcode/sql/dk/formatting/AbstractFormatter.java Fri Dec 20 22:01:06 2013 +0100
@@ -0,0 +1,241 @@
+/**
+ * SQL-DK
+ * Copyright © 2013 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 <http://www.gnu.org/licenses/>.
+ */
+package info.globalcode.sql.dk.formatting;
+
+import info.globalcode.sql.dk.Parameter;
+import java.io.OutputStream;
+import java.util.EmptyStackException;
+import java.util.EnumSet;
+import java.util.List;
+import java.util.Stack;
+
+/**
+ *
+ * @author Ing. František Kučera (frantovo.cz)
+ */
+public abstract class AbstractFormatter implements Formatter {
+
+ private Stack<State> state = new Stack<>();
+ private OutputStream outputStream;
+ private ColumnsHeader currentColumnsHeader;
+ private String currentQuery;
+ private int currentColumnsCount;
+
+ public AbstractFormatter(OutputStream outputStream) {
+ this.outputStream = outputStream;
+ state.push(State.ROOT);
+ }
+
+ /*
+ * root
+ * .database
+ * ..resultSet
+ * ...@query
+ * ...@parameters
+ * ...@columnsHeader
+ * ...row
+ * ....@columnValue
+ * ..updatesResult
+ * ...@query
+ * ...@parameters
+ * ...@updatedRowsCount
+ * ...generatedKeys
+ * ....resultSet (see above)
+ */
+ protected enum State {
+
+ ROOT,
+ DATABASE,
+ RESULT_SET,
+ ROW,
+ UPDATES_RESULT,
+ GENERATED_KEYS
+ }
+
+ /**
+ * Go down in hierarchy.
+ * Pushes new state and verifies the old one.
+ *
+ * @param current the new state – currently entering
+ * @param expected expected previous states (any of them is valid)
+ * @return previous state
+ * @throws IllegalStateException if previous state was not one from expected
+ */
+ private State pushState(State current, EnumSet expected) {
+ State previous = state.peek();
+
+ if (expected.contains(previous)) {
+ state.push(current);
+ return previous;
+ } else {
+ throw new IllegalStateException("Formatter was in wrong state: " + previous + " when it should be in one of: " + expected);
+ }
+ }
+
+ protected State peekState(EnumSet expected) {
+ State current = state.peek();
+
+ if (expected.contains(current)) {
+ return current;
+ } else {
+ throw new IllegalStateException("Formatter is in wrong state: " + current + " when it should be in one of: " + expected);
+ }
+
+ }
+
+ /**
+ * Go up in hierarchy.
+ * Pops the superior state/branch.
+ *
+ * @param expected expected superior state
+ * @return the superior state
+ * @throws IllegalStateException if superior state was not one from expected or if there is no
+ * more superior state (we are at root level)
+ */
+ private State popState(EnumSet expected) {
+ try {
+ State superior = state.pop();
+ if (expected.contains(superior)) {
+ return superior;
+ } else {
+ throw new IllegalStateException("Formatter had wrong superior state: " + superior + " when it should be in one of: " + expected);
+ }
+ } catch (EmptyStackException e) {
+ throw new IllegalStateException("Formatter was already at root level – there is nothing above that.", e);
+ }
+ }
+
+ @Override
+ public void writeStartDatabase() {
+ pushState(State.DATABASE, EnumSet.of(State.ROOT));
+ }
+
+ @Override
+ public void writeEndDatabase() {
+ popState(EnumSet.of(State.ROOT));
+ }
+
+ @Override
+ public void writeStartResultSet() {
+ pushState(State.RESULT_SET, EnumSet.of(State.DATABASE, State.GENERATED_KEYS));
+ }
+
+ @Override
+ public void writeEndResultSet() {
+ popState(EnumSet.of(State.DATABASE, State.GENERATED_KEYS));
+ currentColumnsHeader = null;
+ }
+
+ @Override
+ public void writeQuery(String sql) {
+ peekState(EnumSet.of(State.RESULT_SET, State.UPDATES_RESULT));
+
+ if (currentColumnsHeader == null) {
+ currentQuery = sql;
+ } else {
+ throw new IllegalStateException("Query string '" + sql + "' must be set before columns header – was already set: " + currentColumnsHeader);
+ }
+ }
+
+ @Override
+ public void writeParameters(List<Parameter> parameters) {
+ peekState(EnumSet.of(State.RESULT_SET, State.UPDATES_RESULT));
+
+ if (currentColumnsHeader != null) {
+ throw new IllegalStateException("Parameters '" + parameters + "' must be set before columns header – was already set: " + currentColumnsHeader);
+ }
+
+ if (currentQuery == null) {
+ throw new IllegalStateException("Parameters '" + parameters + "' must be set after query – was not yet set.");
+ }
+ }
+
+ @Override
+ public void writeColumnsHeader(ColumnsHeader header) {
+ peekState(EnumSet.of(State.RESULT_SET, State.UPDATES_RESULT));
+
+ if (currentColumnsHeader == null) {
+ currentColumnsHeader = header;
+ } else {
+ throw new IllegalStateException("Columns header can be set only once per result set – was already set: " + currentColumnsHeader);
+ }
+ }
+
+ @Override
+ public void writeStartRow() {
+ pushState(State.ROW, EnumSet.of(State.RESULT_SET));
+ currentColumnsCount = 0;
+ }
+
+ @Override
+ public void writeEndRow() {
+ popState(EnumSet.of(State.RESULT_SET));
+ }
+
+ @Override
+ public void writeColumnValue(Object value) {
+ peekState(EnumSet.of(State.ROW));
+ currentColumnsCount++;
+
+ int declaredCount = currentColumnsHeader.getColumnCount();
+ if (currentColumnsCount > declaredCount) {
+ throw new IllegalStateException("Current columns count is " + currentColumnsCount + " which is more than declared " + declaredCount + " in header.");
+ }
+ }
+
+ @Override
+ public void writeStartUpdatesResult() {
+ pushState(State.RESULT_SET, EnumSet.of(State.DATABASE));
+ }
+
+ @Override
+ public void writeEndUpdatesResult() {
+ popState(EnumSet.of(State.DATABASE));
+ currentColumnsHeader = null;
+ }
+
+ @Override
+ public void writeUpdatedRowsCount(int updatedRowsCount) {
+ peekState(EnumSet.of(State.UPDATES_RESULT));
+ }
+
+ @Override
+ public void writeStartGeneratedKeys() {
+ pushState(State.GENERATED_KEYS, EnumSet.of(State.UPDATES_RESULT));
+ }
+
+ @Override
+ public void writeEndGeneratedKeys() {
+ popState(EnumSet.of(State.UPDATES_RESULT));
+ }
+
+ protected OutputStream getOutputStream() {
+ return outputStream;
+ }
+
+ protected ColumnsHeader getCurrentColumnsHeader() {
+ return currentColumnsHeader;
+ }
+
+ protected int getCurrentColumnsCount() {
+ return currentColumnsCount;
+ }
+ /**
+ * TODO: write SQLWarning
+ */
+}