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java - 尝试从 Java 中的命令行解析 JSON 时出错

问题描述

我在 pom.xml 中使用 Java 1.8 和以下依赖项：

<dependency>
    <groupId>com.googlecode.json-simple</groupId>
    <artifactId>json-simple</artifactId>
    <version>1.1.1</version>
</dependency>

这是我用 Java 编写的示例命令行应用程序：

import org.json.simple.JSONArray;
import org.json.simple.JSONObject;
import org.json.simple.parser.JSONParser;
import org.json.simple.parser.ParseException;

public class ConsoleApp {

    public static void main(String[] args) throws ParseException {
        if (args.length == 0) {
            System.out.println("Usage: java ConsoleApp jsonString");
            System.exit(0);
        }
        System.out.println(args[0]);
        JSONParser parser = new JSONParser();
        Object obj = parser.parse(args[0]);
        JSONArray array = (JSONArray) obj;
        System.out.println(array.get(1));
    }
}

我的 IntelliJ IDEA 的运行配置：

IntelliJ IDEA 的运行配置

现在，当我运行程序时，这是以下输出：

/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/bin/java "-javaagent:/Applications/IntelliJ IDEA.app/Contents/lib/idea_rt.jar=55033:/Applications/IntelliJ IDEA.app/Contents/bin" -Dfile.encoding=UTF-8 -classpath /Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/charsets.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/deploy.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/ext/cldrdata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/ext/dnsns.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/ext/jaccess.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/ext/jfxrt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/ext/localedata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/ext/nashorn.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/ext/sunec.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/ext/sunjce_provider.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/ext/sunpkcs11.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/ext/zipfs.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/javaws.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/jce.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/jfr.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/jfxswt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/jsse.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/management-agent.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/plugin.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/resources.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/rt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/lib/ant-javafx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/lib/dt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/lib/javafx-mx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/lib/jconsole.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/lib/packager.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/lib/sa-jdi.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/lib/tools.jar:/Users/unnsse_dev/IdeaProjects/ConsoleApp/target/classes:/Users/unnsse_dev/.m2/repository/com/googlecode/json-simple/json-simple/1.1.1/json-simple-1.1.1.jar org.example.ConsoleApp "[ { a:1, b:2 }, { b:3, c:4 }, { c:6, a:5 } ]"
[ { a:1, b:2 }, { b:3, c:4 }, { c:6, a:5 } ]
Exception in thread "main" Unexpected character (L) at position 1.
    at org.json.simple.parser.Yylex.yylex(Yylex.java:610)
    at org.json.simple.parser.JSONParser.nextToken(JSONParser.java:269)
    at org.json.simple.parser.JSONParser.parse(JSONParser.java:118)
    at org.json.simple.parser.JSONParser.parse(JSONParser.java:81)
    at org.json.simple.parser.JSONParser.parse(JSONParser.java:75)
    at org.example.ConsoleApp.main(ConsoleApp.java:17)

Process finished with exit code 1

我可能做错了什么？

我应该使用不同的 JSON 库（例如 Jackson / FasterXML）吗？

标签： javajsonintellij-ideajson-simple

解决方案

传入的程序参数具有未转义的"字符。

尝试

"[ { \"a\":1, \"b\":2 }, { \"b\":3, \"c\":4 }, { \"c\":6, \"a\":5 } ]"

代替

"[ { "a":1, "b":2 }, { "b":3, "c":4 }, { "c":6, "a":5 } ]"

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