抱歉，我在问题中没有发现Log4j是1.x，此答案适用于Log4j 2.x。以下答案仅供可能需要它的人使用：
您可以使用style{pattern}{ANSI style}转换模式，只需将%-30.70C.%-5.20M:%-3.5L更改为%-60style{%-30.70C.%-5.20M:%-3.5L}即可。
简单说明一下，用%-60style{replace-your-pattern-here}把你想格式化的图案部分包起来，然后根据你的情况调整宽度值（这里是60个字符宽度），如果你想彩色输出，只要在style{pattern}后面加上省略的{ANSI style}即可。
下面是Log4j2文档：https://logging.apache.org/log4j/2.x/manual/layouts.html#Patterns

基于@Remko-Popma的帮助
https://issues.apache.org/jira/browse/LOG4J2-2339
以下是对我有效的方法：

<property name="pattern">%d{yyyy-MM-dd HH:mm:ss.SSS} | %-5.5p | %-15.15t | %-70.70CML | %-10.70X | %msg%n</property>

import org.apache.logging.log4j.core.LogEvent;
import org.apache.logging.log4j.core.config.plugins.Plugin;
import org.apache.logging.log4j.core.pattern.ConverterKeys;
import org.apache.logging.log4j.core.pattern.NamePatternConverter;
import org.apache.logging.log4j.core.pattern.PatternConverter;

@Plugin(name = "ClassMethodLinePatternConverter", category = PatternConverter.CATEGORY)
@ConverterKeys({"CML", "classmethodline"})
public class ClassMethodLinePatternConverter extends NamePatternConverter {

    private static final String NA = "?";

    private ClassMethodLinePatternConverter(
        final String[] options) {
        super("Class Name", "class name", options);
    }

    public static ClassMethodLinePatternConverter newInstance(final String[] options) {
        return new ClassMethodLinePatternConverter(options);
    }

    /**
     * Format a logging event.
     *
     * @param event      event to format.
     * @param toAppendTo string buffer to which class name, method name and line will be appended.
     */
    @Override
    public void format(final LogEvent event, final StringBuilder toAppendTo) {
        final StackTraceElement element = event.getSource();
        if (element == null) {
            toAppendTo.append(NA);
        } else {
          toAppendTo.append(element.getClassName()).append(".").append(element.getMethodName()).append(":").append(element.getLineNumber());
        }
    }

}