使用字符串常量池,每当我们使用字面量(String s=”1”;)创建字符串常量时,JVM会首先检查字符串常量池,如果该字符串已经存在常量池中,那么就将此字符串对象的地址赋值给引用s(引用s在Java栈中)。如果字符串不存在常量池中,就会实例化该字符串并且将其放到常量池中,并将此字符串对象的地址赋值给引用s
#48 // java/lang/System.out:Ljava/io/PrintStream; #13 = Methodref #49.#50 // java/io/PrintStream.println:(Z)V #14 = Class #51 // Others/base/StringDemo4 #15 = Class #52 // java/lang/Object #16 = Utf8 <init> #17 = Utf8 ()V #18 = Utf8 Code #19 = Utf8 ...
Hashcode Of A String In Java Many of the Java programmers know what 'Hashcode' means, but don't really know how exactly it is calculated and why 31 is used to calculate the hashcode. Below is the code snippet from Java 1.6, which calculates the hashcode for a string: publicinthashCode()...
initially empty, is maintained privately by the * class {@code String}. * <p> * When the intern method is invoked, if the pool already contains a * string equal to this {@code String} object as determined by * the {@link #equals(Object)} ...
publicclasscom.justin.java.lang.InternTest{ publiccom.justin.java.lang.InternTest();Code:: aload_0 1: invokespecial #1// Method java/lang/Object."<init>":()V4:returnpublicstaticvoidmain(java.lang.String[]);Code::new #2// class java/lang/StringBuilder3: dup 4: invokespecial #3...
public final class String implements java.io.Serializable, Comparable<String>, CharSequence, Constable, ConstantDesc { @Stable private final byte[] value; //字符串实际上就存储在这个用final修饰的byte数组中private final byte coder; /** Cache the hash code for the string */ private int hash; /...
private String countryCode; private double longitude; private double latitude; } 1. 2. 3. 4. 5. 6. 7. 考虑到其中有很多用户在地址信息上是有重合的,比如,国家、省份、城市等, 这时就可以将这部分信息单独列出一个类,以减少重复,代码如下:
String(int[] codePoints, int offset, int count) 分配一个新的String,它包含 Unicode 代码点数组参数一个子数组的字符。 String(Stringoriginal) 初始化一个新创建的String对象,使其表示一个与参数相同的字符序列;换句话说,新创建的字符串是该参数字符串的副本。
1,JAVA 代码 /** * Returns a canonical representation for the string object. *<p>* A pool of strings, initially empty, is maintained privately by the * class<code>String</code>. *<p>* When the intern method is invoked, if the pool already contains a ...
Sample code for analysis: @Slf4j public class StringConcat { @SneakyThrows public static void main(String[] args) { log.info("java虚拟机预热开始"); String[] strs = new String[6000000]; for (int i = 0; i < strs.length; i++) { ...