Question

当我尝试运行时，它表示console.readLine();存在问题。

import java.io.Console;

public class PingPong {
public static void main(String[] args) {
    System.out.println("give me a number, honey?");
    String stringYourNumber = console.readLine();
    Integer yourNumber = Integer.parseInt(stringYourNumber);

    System.out.println("Here ya go:");
    for ( Integer i=1; i <=yourNumber; i++){
        if( i % 5==0 && i % 3==0){
            System.out.println("PingPong");
        } else {
            if (i % 5==0){
                System.out.println("Pong");
            } else {
                if ( i % 3==0){
                    System.out.println("Ping");
                }
            }
        }
    }
}

Answer 1

您必须声明并初始化名为console

的变量

Console console = System.console();
if (console != null)  {
    str = console.readline ();
}

Answer 2

我对这个问题进行了一些研究。以下是解决方案。

import java.io.Console;

#!/bin/bash

# pre-commit hook to comb staged .sass and .scss files
# save as .git/hooks/pre-commit
# make executable: chmod +x .git/hooks/pre-commit

# sources:

# http://www.hagenburger.net/BLOG/Using-Git-Commit-Hooks-to-Autocompile-Sass-to-CSS.html
# http://stackoverflow.com/questions/8470755/git-pre-commit-hook-add-file-into-index/8471009#8471009
# http://stackoverflow.com/questions/592620/how-to-check-if-a-program-exists-from-a-bash-script/677212#677212
# https://gist.github.com/openam/8406343

# check if sass/scss files are staged for commit

# diff-lines from http://stackoverflow.com/a/12179492/3019532
# takes the line
function diff-lines() {
    local path=
    local line=
    while read; do
        esc=$'\033'
        if [[ $REPLY =~ ---\ (a/)?.* ]]; then
            continue
        elif [[ $REPLY =~ \+\+\+\ (b/)?([^[:blank:]$esc]+).* ]]; then
            path=${BASH_REMATCH[2]}
        elif [[ $REPLY =~ @@\ -[0-9]+(,[0-9]+)?\ \+([0-9]+)(,[0-9]+)?\ @@.* ]]; then
            line=${BASH_REMATCH[2]}
        elif [[ $REPLY =~ ^($esc\[[0-9;]+m)*([\ +-]) ]]; then
            echo "Line $line:$REPLY"
            if [[ ${BASH_REMATCH[2]} != - ]]; then
                ((line++))
            fi
        fi
    done
}

if ! git diff --quiet --cached -- **/*.{sass,scss}; then

            echo ""
            echo "--> you checked in sass/scss files. lets comb them..."
            echo ""

            # check if csscomb is installed

            if hash csscomb 2>/dev/null; then

                echo -e "\033[1;32m--> found csscomb\033[0m"

                # TODO: check for csscomb update once a week

                # check if configfile exists

                if [ ! -f ./.csscomb.json ]; then
                    echo "--> no config file, using defaults"
                else
                    echo -e "\033[1;32m--> found .csscomb.json\033[0m"
                fi

                echo ""

                # Necessary check for initial commit
                against="4b825dc642cb6eb9a060e54bf8d69288fbee4904"
                git rev-parse --verify HEAD >/dev/null 2>&1 && against="HEAD"
                EXITCODE=0

                # (A)dded (C)opied or (M)odified
                # encapsulate the loop in {} http://stackoverflow.com/a/13665483/3019532
                git diff-index --cached --full-index --diff-filter=ACM $against | \
                {
                    while read -r line; do
                      FILE_PATH="$(echo ${line} |cut -d' ' -f6-)"
                      EXTENSION="${FILE_PATH##*.}"
                      # EXTENSION=${EXTENSION,,} # Convert to lowercase
                      REGEX=""

                      # Select discouraged words based on extension

                      if [ "${EXTENSION}" = "sass" ] || [ "${EXTENSION}" = "scss" ]; then
                        echo "--> staged sass/scss file: " $FILE_PATH
                        echo "--> combing..."
                        if csscomb $FILE_PATH; then
                            echo "--> adding combed file"
                            git add $FILE_PATH
                            echo "--> done"
                        else
                            echo "Check your CSS file for combing errors or alternatively add '-n' to your git commit to bypass this hook"
                            break
                            exit 1 # Should stop the git commit from continuing
                        fi
                      fi
                    done
                }
            else
                echo -e "\033[0;31m--> Oh noes, CSS Comb is not installed. Do:"
                echo "--> npm install csscomb -g"
                echo -e "\033[0m"
                echo "--> (you need to change and stage a sass/scss file again to see it work on the next commit...)"
                echo ""
            fi
fi

# Necessary check for initial commit
against="4b825dc642cb6eb9a060e54bf8d69288fbee4904"
git rev-parse --verify HEAD >/dev/null 2>&1 && against="HEAD"
EXITCODE=0

exit 0

您使用代码的方法实际上是C＃的原生方法。但是，这个功能也可以在这里调整。但是现在你接下来的工作就是找到如何进入java的控制台。另请注意，我们并未将控制台视为一个类，而是将其作为内置函数。您可以通过我们没有使用新的Console（）创建任何对象来确定。

我希望这会对你有所帮助。

console.readLine（）;出错但是代码中的一切看起来都正确

2 个答案: