CaseInsensitiveStream.java

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// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
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// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.

package org.apache.doris.nereids.parser;

import org.antlr.v4.runtime.CharStream;
import org.antlr.v4.runtime.IntStream;
import org.antlr.v4.runtime.misc.Interval;

/**
 * Translate parser stream to insensitive.
 */
public class CaseInsensitiveStream implements CharStream {
    private final CharStream stream;

    public CaseInsensitiveStream(CharStream stream) {
        this.stream = stream;
    }

    @Override
    public String getText(Interval interval) {
        return stream.getText(interval);
    }

    @Override
    public void consume() {
        stream.consume();
    }

    @Override
    public int LA(int i) {
        int result = stream.LA(i);

        switch (result) {
            case 0:
            case IntStream.EOF:
                return result;
            default:
                return Character.toUpperCase(result);
        }
    }

    @Override
    public int mark() {
        return stream.mark();
    }

    @Override
    public void release(int marker) {
        stream.release(marker);
    }

    @Override
    public int index() {
        return stream.index();
    }

    @Override
    public void seek(int index) {
        stream.seek(index);
    }

    @Override
    public int size() {
        return stream.size();
    }

    @Override
    public String getSourceName() {
        return stream.getSourceName();
    }
}