标题翻译
Kotlin String max length? (Kotlin file with a long String is not compiling)
问题
根据这个答案，Java 可以容纳最多 2^31 - 1 个字符。我试图进行基准测试等操作，所以我尝试创建大量的字符串，并将其写入文件，就像这样：
import java.io.*
fun main() {
val out = File("ouput.txt").apply { createNewFile() }.printWriter()
sequence {
var x = 0
while (true) {
yield("${++x} ${++x} ${++x} ${++x} ${++x}")
}
}.take(5000).forEach { out.println(it) }
out.close()
}
然后 output.txt 文件的内容如下所示：
1 2 3 4 5
6 7 8 9 10
11 12 13 14 15
16 17 18 19 20
21 22 23 24 25
// ... 5000 行
然后我将文件的所有内容复制到一个字符串中，以便对某些函数进行基准测试，代码如下：
import kotlin.system.*
fun main() {
val inputs = """
1 2 3 4 5
6 7 8 9 10
11 12 13 14 15
16 17 18 19 20
21 22 23 24 25
// ... 5000 行
24986 24987 24988 24989 24990
24991 24992 24993 24994 24995
24996 24997 24998 24999 25000
""".trimIndent()
measureNanoTime {
inputs.reader().forEachLine { line ->
val (a, b, c, d, e) = line.split(" ").map(String::toInt)
}
}.div(5000).let(::println)
}
> 文件/字符串的总字符数为 138894
>
> 字符串最多可以容纳 2147483647 个字符
但是 Kotlin 代码无法编译（最后的文件） 它抛出编译错误：
e: org.jetbrains.kotlin.codegen.CompilationException: Back-end (JVM) Internal error: wrong bytecode generated
// 更多行
The root cause java.lang.IllegalArgumentException was thrown at: org.jetbrains.org.objectweb.asm.ByteVector.putUTF8(ByteVector.java:246)
at org.jetbrains.kotlin.codegen.TransformationMethodVisitor.visitEnd(TransformationMethodVisitor.kt:92)
at org.jetbrains.kotlin.codegen.FunctionCodegen.endVisit(FunctionCodegen.java:971)
... 43 more
Caused by: java.lang.IllegalArgumentException: UTF8 string too large
这是异常的完整日志和堆栈跟踪：https://gist.github.com/Animeshz/1a18a7e99b0c0b913027b7fb36940c07
英文翻译
According to this answer Java can hold up to 2^31 - 1 characters. I was trying to do benchmarking and stuffs, so I tried to create a large amount of string and write it to a file like this:
import java.io.*
fun main() {
val out = File("ouput.txt").apply { createNewFile() }.printWriter()
sequence {
var x = 0
while (true) {
yield("${++x} ${++x} ${++x} ${++x} ${++x}")
}
}.take(5000).forEach { out.println(it) }
out.close()
}
And then the output.txt file contains like this:
1 2 3 4 5
6 7 8 9 10
11 12 13 14 15
16 17 18 19 20
21 22 23 24 25
// ... 5000 lines
And then I copied all the contents of the file into a string for some benchmarking of some functions, so this is how it looks:
import kotlin.system.*
fun main() {
val inputs = """
1 2 3 4 5
6 7 8 9 10
11 12 13 14 15
16 17 18 19 20
21 22 23 24 25
// ... 5000 lines
24986 24987 24988 24989 24990
24991 24992 24993 24994 24995
24996 24997 24998 24999 25000
""".trimIndent()
measureNanoTime {
inputs.reader().forEachLine { line ->
val (a, b, c, d, e) = line.split(" ").map(String::toInt)
}
}.div(5000).let(::println)
}
> The total character count of the file/string is 138894
>
> String can hold up to 2147483647
But the Kotlin code does not compile (last file) It throws compilation error:
e: org.jetbrains.kotlin.codegen.CompilationException: Back-end (JVM) Internal error: wrong bytecode generated
// more lines
The root cause java.lang.IllegalArgumentException was thrown at: org.jetbrains.org.objectweb.asm.ByteVector.putUTF8(ByteVector.java:246)
at org.jetbrains.kotlin.codegen.TransformationMethodVisitor.visitEnd(TransformationMethodVisitor.kt:92)
at org.jetbrains.kotlin.codegen.FunctionCodegen.endVisit(FunctionCodegen.java:971)
... 43 more
Caused by: java.lang.IllegalArgumentException: UTF8 string too large
Here is the total log of exception with stacktrace: https://gist.github.com/Animeshz/1a18a7e99b0c0b913027b7fb36940c07
答案1
得分: 4
在Java类文件中有限制，字符串常量的长度必须适应16位，即源代码中的字符串最大长度为65535字节（而不是字符）。
英文翻译
There is limit in java class file, length of string constant must fit in 16 bits ie. 65535 bytes (not characters) is max length of string in source code.
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