[2022 中国 DevOps 现状调查全面启动！>>>

字符串截取下标越界

java.lang.StringIndexOutOfBoundsException: String index out of range: -1at java.lang.String.substring(String.java:1967)

出错代码

result.put("value", valueBuilder.toString().substring(0,valueBuilder.toString().length()-1));

修改后代码

if (StringUtils.isNotBlank(valueBuilder.toString()) && valueBuilder.toString().length() >0){result.put("value", valueBuilder.toString().substring(0,valueBuilder.toString().length()-1));}

总结

StringIndexOutOfBoundsException 异常源码如下：

/*** Thrown by {@code String} methods to indicate that an index* is either negative or greater than the size of the string.  For* some methods such as the charAt method, this exception also is* thrown when the index is equal to the size of the string.*/
public
class StringIndexOutOfBoundsException extends IndexOutOfBoundsException {private static final long serialVersionUID = -6762910422159637258L;/*** Constructs a {@code StringIndexOutOfBoundsException} with no* detail message.** @since   JDK1.0.*/public StringIndexOutOfBoundsException() {super();}/*** Constructs a {@code StringIndexOutOfBoundsException} with* the specified detail message.** @param   s   the detail message.*/public StringIndexOutOfBoundsException(String s) {super(s);}/*** Constructs a new {@code StringIndexOutOfBoundsException}* class with an argument indicating the illegal index.** @param   index   the illegal index.*/public StringIndexOutOfBoundsException(int index) {super("String index out of range: " + index);}
}

总共有以下几个方法会抛出该异常：

String.substring()String.charAt()String.codePointAt()String.codePointBefore()String.subSequence()String.getChars()String.getBytes()