使用带填充的java创建文本文件表

因为我的上一篇文章和问题非常模糊，这里是我现在的来源和一个更清晰的问题。现在一切都是关于填充的

以下是我目前的代码：

import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;

public class makeTable {


static ArrayList<String> val1 = new ArrayList<>(Arrays.asList("field1", "field1val2", "field1val3"));
static ArrayList<String> val2 = new ArrayList<>(Arrays.asList("field2", "field2val2", "field2val3"));
static int col1=15;
static int col2=15;

public static void main(String arg[]) {

BufferedWriter writeTable = null;
try {
    writeTable = new BufferedWriter(new FileWriter("C:/testtable.txt"));

    //Anfang erste Zeile
    writeTable.write("+ ");
    for (int i = 0; i < col1; i++){
        writeTable.write("-");   
    }
    writeTable.write(" + ");
    for (int i = 0; i < col2; i++){
        writeTable.write("-");   
    }
    writeTable.write(" +");
    writeTable.newLine();
    //Ende erste Zeile

    for (int i = 0; i < val1.size(); i++){
        writeTable.write("| " + val1.get(i) + "   "+ " + " +"   "+ val2.get(i) +  "   "+ " |");
        writeTable.newLine();

        writeTable.write("+ ");
        for (int j = 0; j < col1; j++){
            writeTable.write("-");   
        }
        writeTable.write(" + ");
        for (int m = 0; m < col2; m++){
            writeTable.write("-");   
        }
        writeTable.write(" +");
        writeTable.newLine(); 

    }
} catch (IOException e) {
    System.err.println(e);
} finally {
    if (writeTable != null) {
        try {
            writeTable.close();
        } catch (IOException e) {
            System.err.println(e);
        }
    }
}
}
}

等等。它需要居中。我只能考虑添加像val1.get（I）.length（）/2这样的内容，这就是要添加的“”的数量。。。。但是我怎么能做到呢

---

我无法使用其他库（第三方库）。

在下面的代码中，使用

StringBuilder

和

BufferedWriter

更改

append

public void appendCentered(StringBuilder sb, String s, int width) {
    if (s.length() > width) {
        s = s.substring(0, width);
    }
    int spaces = width - s.length();
    int before = spaces / 2;
    int after = spaces - before; // Could be 1 more than 'before'.
    appendSpaces(sb, before);
    sb.append(s);
    appendSpaces(sb, after);
}

public void appendSpaces(StringBuilder sb, int width) {
    while (width-- > 0) {
        sb.append(' ');
    }
}

---

以下是我将文本居中后的程序结果

+ -------------- + -------------- +
|     field1     +     field2     |
+ -------------- + -------------- +
|   field1val2   +   field2val2   |
+ -------------- + -------------- +
|   field1val3   +   field2val3   |
+ -------------- + -------------- +

这是我做的改动

我做的最大的一件事就是把你的单片代码分解成方法。通过编写小方法，您可以将较大的任务分解为较小的任务。较小的任务更容易编码

类名以大写字母开头。我将makeTable重命名为makeTable

我将您的代码更改为使用列表接口，而不是ArrayList类。通过使用该接口，将来更容易更改列表的类型。我可以通过更改两行代码来使用LinkedList

main方法现在只创建输出。我无法直接写入Windows8.1笔记本电脑上的C驱动器。我必须在与代码相同的目录中创建该文件

WritedShedline方法写入一条虚线。我在两个地方使用代码，但是通过将代码放入一个方法中，我只需编写一次代码

writeDashes方法写入虚线的虚线部分。同样，我在两个地方使用代码，但是通过将代码放入一个方法中，我只需编写一次代码

writeValueLine方法将值写入一行。我只在一个地方使用代码，但为了与writedShedline方法保持一致，我为代码编写了一个方法

其余的方法都是我写的中心文本。首先，我在两个值列表中找到了最长的值。接下来，我添加了4个填充字符。接下来，我通过在字符串的前面和后面添加填充来居中显示文本

研究这些方法，以便将来可以完成此类任务

这是格式化的代码

package com.ggl.testing;

import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class MakeTable {

    static List<String> val1 = new ArrayList<>(Arrays.asList("field1",
            "field1val2", "field1val3"));
    static List<String> val2 = new ArrayList<>(Arrays.asList("field2",
            "field2val2", "field2val3"));

    static int length = getLongestValue(val1, val2) + 4;

    public static void main(String arg[]) {

        BufferedWriter writeTable = null;
        try {
            writeTable = new BufferedWriter(new FileWriter("testtable.txt"));

            writeDashedLine(writeTable);
            writeTable.newLine();
            // Ende erste Zeile

            for (int i = 0; i < val1.size(); i++) {
                writeValueLine(writeTable, val1.get(i), val2.get(i));
                writeTable.newLine();

                writeDashedLine(writeTable);
                writeTable.newLine();

            }
        } catch (IOException e) {
            System.err.println(e);
        } finally {
            if (writeTable != null) {
                try {
                    writeTable.close();
                } catch (IOException e) {
                    System.err.println(e);
                }
            }
        }
    }

    public static void writeDashedLine(BufferedWriter writeTable)
            throws IOException {
        // Anfang erste Zeile
        writeTable.write("+ ");
        writeDashes(writeTable);
        writeTable.write(" + ");
        writeDashes(writeTable);
        writeTable.write(" +");
    }

    public static void writeDashes(BufferedWriter writeTable)
            throws IOException {
        for (int i = 0; i < length; i++) {
            writeTable.write("-");
        }
    }

    public static void writeValueLine(BufferedWriter writeTable, String value1,
            String value2) throws IOException {
        writeTable.write("| " + centerText(value1, length) + " + "
                + centerText(value2, length) + " |");
    }

    public static String centerText(String text, int length) {
        int textLength = text.length();
        if (textLength > length) {
            return text.substring(0, length);
        } else if (textLength == length) {
            return text;
        } else {
            int diff1 = (length - textLength) / 2;
            int diff2 = length - textLength - diff1;
            return getPadding(' ', diff1) + text + getPadding(' ', diff2);
        }
    }

    public static String getPadding(char pad, int length) {
        String padding = "";

        for (int i = 0; i < length; i++) {
            padding += pad;
        }

        return padding;
    }

    public static int getLongestValue(List<String> val1, List<String> val2) {
        int length = 0;

        for (String s : val1) {
            length = Math.max(length, s.length());
        }

        for (String s : val2) {
            length = Math.max(length, s.length());
        }

        return length;
    }
}

package com.ggl.testing；
导入java.io.BufferedWriter；
导入java.io.FileWriter；
导入java.io.IOException；
导入java.util.ArrayList；
导入java.util.array；
导入java.util.List；
公共类生成表{
静态列表val1=新的ArrayList（Arrays.asList（“field1”），
“field1val2”、“field1val3”）；
静态列表val2=新的ArrayList（Arrays.asList（“field2”），
“field2val2”、“field2val3”）；
静态int-length=getLongestValue（val1，val2）+4；
公共静态void main（字符串arg[]）{
BufferedWriter writeTable=null；
试一试{
writeTable=新的BufferedWriter（新的FileWriter（“testtable.txt”）；
可写数据线（可写）；
writeTable.newLine（）；
//恩德·厄斯特·泽勒
对于（int i=0；i长度）{
返回text.substring（0，长度）；
}else if（textLength==长度）{
返回文本；
}否则{
int diff1=（length-textLength）/2；
int diff2=长度-文本长度-diff1；
返回getPadding（“”，diff1）+text+getPadding（“”，diff2）；
}
}
公共静态字符串getPadding（字符填充，int-length）{
字符串填充=”；
for（int i=0；i

您的问题到底是什么？如何写入文件？或者如何获取该模式？主要是如何获取具有值的表的模式。这个小库可能会有所帮助：@Marged assylias在我指定无法使用其他库之前写了这条评论，这就是我添加该问题的原因。

package com.ggl.testing;

import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class MakeTable {

    static List<String> val1 = new ArrayList<>(Arrays.asList("field1",
            "field1val2", "field1val3"));
    static List<String> val2 = new ArrayList<>(Arrays.asList("field2",
            "field2val2", "field2val3"));

    static int length = getLongestValue(val1, val2) + 4;

    public static void main(String arg[]) {

        BufferedWriter writeTable = null;
        try {
            writeTable = new BufferedWriter(new FileWriter("testtable.txt"));

            writeDashedLine(writeTable);
            writeTable.newLine();
            // Ende erste Zeile

            for (int i = 0; i < val1.size(); i++) {
                writeValueLine(writeTable, val1.get(i), val2.get(i));
                writeTable.newLine();

                writeDashedLine(writeTable);
                writeTable.newLine();

            }
        } catch (IOException e) {
            System.err.println(e);
        } finally {
            if (writeTable != null) {
                try {
                    writeTable.close();
                } catch (IOException e) {
                    System.err.println(e);
                }
            }
        }
    }

    public static void writeDashedLine(BufferedWriter writeTable)
            throws IOException {
        // Anfang erste Zeile
        writeTable.write("+ ");
        writeDashes(writeTable);
        writeTable.write(" + ");
        writeDashes(writeTable);
        writeTable.write(" +");
    }

    public static void writeDashes(BufferedWriter writeTable)
            throws IOException {
        for (int i = 0; i < length; i++) {
            writeTable.write("-");
        }
    }

    public static void writeValueLine(BufferedWriter writeTable, String value1,
            String value2) throws IOException {
        writeTable.write("| " + centerText(value1, length) + " + "
                + centerText(value2, length) + " |");
    }

    public static String centerText(String text, int length) {
        int textLength = text.length();
        if (textLength > length) {
            return text.substring(0, length);
        } else if (textLength == length) {
            return text;
        } else {
            int diff1 = (length - textLength) / 2;
            int diff2 = length - textLength - diff1;
            return getPadding(' ', diff1) + text + getPadding(' ', diff2);
        }
    }

    public static String getPadding(char pad, int length) {
        String padding = "";

        for (int i = 0; i < length; i++) {
            padding += pad;
        }

        return padding;
    }

    public static int getLongestValue(List<String> val1, List<String> val2) {
        int length = 0;

        for (String s : val1) {
            length = Math.max(length, s.length());
        }

        for (String s : val2) {
            length = Math.max(length, s.length());
        }

        return length;
    }
}