com.sangupta.fileanalysis.formats.base.AbstractDelimitedFileFormatHandler.java Source code

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Here is the source code for com.sangupta.fileanalysis.formats.base.AbstractDelimitedFileFormatHandler.java

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/**
 *
 * FileAnalysis - SQLize files to analyze dumps and logs
 * Copyright (c) 2014-2015, Sandeep Gupta
 * 
 * http://sangupta.com/projects/fileanalysis
 * 
 * Licensed 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 "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * 
 */

package com.sangupta.fileanalysis.formats.base;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import org.apache.commons.io.FileUtils;
import org.apache.commons.io.LineIterator;

import com.sangupta.fileanalysis.db.DBColumn;
import com.sangupta.fileanalysis.db.DBColumnType;
import com.sangupta.fileanalysis.db.DBHelper;
import com.sangupta.fileanalysis.db.Database;
import com.sangupta.fileanalysis.db.DatabaseTable;
import com.sangupta.jerry.util.AssertUtils;
import com.sangupta.jerry.util.ConsoleUtils;
import com.sangupta.jerry.util.StringUtils;

/**
 * Base class for file format handlers where fields are terminated using a
 * delimiter.
 * 
 * @author sangupta
 *
 */
public abstract class AbstractDelimitedFileFormatHandler extends AbstractFileFormatHandler {

    /**
     * Read line by line from file
     */
    private LineIterator iterator;

    /**
     * The database table
     */
    private DatabaseTable table;

    /**
     * Has header row
     */
    private boolean hasHeaderRow = true;

    /**
     * Stores the first line if needed
     */
    private String firstLine;

    /**
     * Get the delimiter string.
     * 
     * @return
     */
    protected abstract String getDelimiterString();

    /**
     * Initialize the handler
     */
    @Override
    public void initialize(Database database, File file) {
        super.setDBAndFile(database, file);

        try {
            iterator = FileUtils.lineIterator(this.file);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    /**
     * Read user based configuration
     */
    @Override
    public void readConfiguration() {
        this.hasHeaderRow = StringUtils.getBoolean(
                ConsoleUtils.readLine("Data has header row (" + this.hasHeaderRow + "): ", true),
                this.hasHeaderRow);
    }

    /**
     * Create the database tables.
     * 
     */
    public void createDBTables() {
        this.table = new DatabaseTable("data");
        List<DBColumn> columns = extractColumns();
        for (DBColumn column : columns) {
            table.addColumn(column);
        }

        database.dropTable(table);
        database.createTable(table);
    }

    /**
     * Find out the columns that are needed.
     * 
     * @return
     */
    protected List<DBColumn> extractColumns() {
        String line = this.iterator.next();
        if (line == null) {
            return null;
        }

        // store first line for insertion if no header row
        if (!this.hasHeaderRow) {
            this.firstLine = line;
        }

        // parse the line
        List<DBColumn> columns = new ArrayList<DBColumn>();
        String[] tokens = org.apache.commons.lang3.StringUtils.splitByWholeSeparator(line, getDelimiterString());
        for (String token : tokens) {
            if (AssertUtils.isBlank(token)) {
                columns.add(new DBColumn("col", DBColumnType.STRNG));
                continue;
            }

            columns.add(new DBColumn(token, DBHelper.detectColumnType(token)));
        }

        return columns;
    }

    /**
     * Load the file
     */
    @Override
    public void loadFile() throws IOException {
        String[] lineItems;
        String line;

        if (firstLine != null) {
            lineItems = org.apache.commons.lang3.StringUtils.splitByWholeSeparator(firstLine, getDelimiterString());
            insertRow(this.table, lineItems);
        }

        while (iterator.hasNext()) {
            line = iterator.next();

            if (AssertUtils.isBlank(line)) {
                continue;
            }

            lineItems = org.apache.commons.lang3.StringUtils.splitByWholeSeparator(line, getDelimiterString());
            insertRow(this.table, lineItems);
        }
    }

}