ShellTable.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file 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 "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 net.lr.karaf.jms.command;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class ShellTable {
    public List<String> header = new ArrayList<String>();
    public List<List<String>> content = new ArrayList<List<String>>();
    public int maxColSize = 25;
    
    public List<String> addRow() {
        List<String> row = new ArrayList<String>();
        content.add(row);
        return row;
    }
    
    public void print()  {
        int[] sizes = new int[header.size()];
        updateSizes(sizes, header);
        for (List<String> row : content) {
            updateSizes(sizes, row);
        }
        String headerLine = getRow(sizes, header, " | ");
        System.out.println(headerLine);
        System.out.println(underline(headerLine.length()));
        for (List<String> row : content) {
            System.out.println(getRow(sizes, row, " | "));
        }
    }

    private String underline(int length) {
        char[] exmarks = new char[length];
        Arrays.fill(exmarks, '-');
        return new String(exmarks);
    }

    private String getRow(int[] sizes, List<String> row, String separator) {
        StringBuilder line = new StringBuilder();
        int c = 0;
        for (String cell : row) {
            if (cell == null) {
                cell = "";
            }
            if (cell.length() > maxColSize) {
                cell = cell.substring(0, maxColSize -1);
            }
            cell = cell.replaceAll("\n", "");
            line.append(String.format("%-" + sizes[c] + "s", cell));
            if (c + 1 < row.size()) {
                line.append(separator);
            }
            c++;
        }
        return line.toString();
    }

    private void updateSizes(int[] sizes, List<String> row) {
        int c = 0;
        for (String cellContent : row) {
            int cellSize = cellContent != null ? cellContent.length() : 0;
            cellSize = Math.min(cellSize, maxColSize);
            if (cellSize > sizes[c]) {
                sizes[c] = cellSize;
            }
            c++;
        }
    }
}