org.h2.value.ValueResultSet Maven / Gradle / Ivy
/*
* Copyright 2004-2011 H2 Group. Multiple-Licensed under the H2 License,
* Version 1.0, and under the Eclipse Public License, Version 1.0
* (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.value;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import org.h2.message.DbException;
import org.h2.tools.SimpleResultSet;
import org.h2.util.StatementBuilder;
/**
* Implementation of the RESULT_SET data type.
*/
public class ValueResultSet extends Value {
private final ResultSet result;
private ValueResultSet(ResultSet rs) {
this.result = rs;
}
/**
* Create a result set value for the given result set.
* The result set will be wrapped.
*
* @param rs the result set
* @return the value
*/
public static ValueResultSet get(ResultSet rs) {
ValueResultSet val = new ValueResultSet(rs);
return val;
}
/**
* Create a result set value for the given result set. The result set will
* be fully read in memory. The original result set is not closed.
*
* @param rs the result set
* @param maxrows the maximum number of rows to read (0 to just read the
* meta data)
* @return the value
*/
public static ValueResultSet getCopy(ResultSet rs, int maxrows) {
try {
ResultSetMetaData meta = rs.getMetaData();
int columnCount = meta.getColumnCount();
SimpleResultSet simple = new SimpleResultSet();
simple.setAutoClose(false);
ValueResultSet val = new ValueResultSet(simple);
for (int i = 0; i < columnCount; i++) {
String name = meta.getColumnLabel(i + 1);
int sqlType = meta.getColumnType(i + 1);
int precision = meta.getPrecision(i + 1);
int scale = meta.getScale(i + 1);
simple.addColumn(name, sqlType, precision, scale);
}
for (int i = 0; i < maxrows && rs.next(); i++) {
Object[] list = new Object[columnCount];
for (int j = 0; j < columnCount; j++) {
list[j] = rs.getObject(j + 1);
}
simple.addRow(list);
}
return val;
} catch (SQLException e) {
throw DbException.convert(e);
}
}
public int getType() {
return Value.RESULT_SET;
}
public long getPrecision() {
return Integer.MAX_VALUE;
}
public int getDisplaySize() {
// it doesn't make sense to calculate it
return Integer.MAX_VALUE;
}
public String getString() {
try {
StatementBuilder buff = new StatementBuilder("(");
result.beforeFirst();
ResultSetMetaData meta = result.getMetaData();
int columnCount = meta.getColumnCount();
for (int i = 0; result.next(); i++) {
if (i > 0) {
buff.append(", ");
}
buff.append('(');
buff.resetCount();
for (int j = 0; j < columnCount; j++) {
buff.appendExceptFirst(", ");
int t = DataType.convertSQLTypeToValueType(meta.getColumnType(j + 1));
Value v = DataType.readValue(null, result, j+1, t);
buff.append(v.getString());
}
buff.append(')');
}
result.beforeFirst();
return buff.append(')').toString();
} catch (SQLException e) {
throw DbException.convert(e);
}
}
protected int compareSecure(Value v, CompareMode mode) {
throw throwUnsupportedExceptionForType("<=>");
}
public boolean equals(Object other) {
return other == this;
}
public int hashCode() {
return 0;
}
public Object getObject() {
return result;
}
public ResultSet getResultSet() {
return result;
}
public void set(PreparedStatement prep, int parameterIndex) {
throw throwUnsupportedExceptionForType("PreparedStatement.set");
}
public String getSQL() {
return "";
}
public Value convertPrecision(long precision, boolean force) {
if (!force) {
return this;
}
return ValueResultSet.get(new SimpleResultSet());
}
}