package com.cedric.thinkingInJava.test;class Person{String name;int age;
}public class ReferenceAndArgs {public static void main(String[] args) {Person person=new Person();Person personBeforeChangeAge;setPersonInfo(person);personBeforeChangeAge=person;System.out.println("Before the change:");printPersonInfo(personBeforeChangeAge);System.out.println("After the change:");changeTheAge(person);printPersonInfo(person);printPersonInfo(personBeforeChangeAge);//这里可以认为所有的引用都指向了最初的new Person()这个对象
    }static void setPersonInfo(Person person) {person.name="nerd";person.age=22;}static void printPersonInfo(Person person) {System.out.println(person.name+" "+person.age);}static void changeTheAge(Person person) {person.age++;printPersonInfo(person);}
}

package com.cedric.thinkingInJava.test;
public class test {static void numberIncreaseByOne(String number){number=new String("2");printNumber(number);}static void printNumber(String number) {System.out.println(number);}public static void main(String[] args) {String integer=new String("1");numberIncreaseByOne(integer);printNumber(integer);        }
}

public final class Stringimplements java.io.Serializable, Comparable<String>, CharSequence
{/** The value is used for character storage. */private final char value[];/** The offset is the first index of the storage that is used. */private final int offset;/** The count is the number of characters in the String. */private final int count;
……

abstract class AbstractStringBuilder implements Appendable, CharSequence {/*** The value is used for character storage.*/char value[];/** * The count is the number of characters used.*/int count;/** * This no-arg constructor is necessary for serialization of subclasses.*/AbstractStringBuilder() {
}