Foreach循环中的Foreach循环(Java)
我有以下代码:Foreach循环中的Foreach循环(Java),java,loops,Java,Loops,我有以下代码: Set<TOrganization> organizations = new LinkedHashSet<TOrganization>(); Set<TRole> roles = new LinkedHashSet<TRole>(); StringBuilder message = new StringBuilder("Requested roles: " + "\n"); //I fill them up with names
Set<TOrganization> organizations = new LinkedHashSet<TOrganization>();
Set<TRole> roles = new LinkedHashSet<TRole>();
StringBuilder message = new StringBuilder("Requested roles: " + "\n");
//I fill them up with names like Test org A, Test Role A 1
for(TOrganization org : organizations) {
message.append(" - " + org.getName()+ "\n");
for(TRole role : roles) {
if(role.getOrganization().equals(org)) {
message.append(" - " + role.getName()+ "\n");
}
}
}
Set organizations=newlinkedhashset();
Set roles=new LinkedHashSet();
StringBuilder消息=新的StringBuilder(“请求的角色:“+”\n”);
//我用诸如测试组织A、测试角色A 1之类的名称填充它们
for(组织机构:组织){
message.append(“-”+org.getName()+”\n”);
for(TRole角色:角色){
if(role.getOrganization().equals(org)){
message.append(“-”+角色.getName()+”\n”);
}
}
}
我想打印出不同类别中的角色,如下所示:
“-测试组织A”“-测试角色A 1”
“-测试角色A 2”
“-测试组织B”
“-测试角色B 1”
“-测试角色B 2” 但我的代码总是在角色之前附加组织名称,如下所示: “-测试组织A”
“-测试角色A 1”
“-测试组织A”
“-测试角色A 2”
“-测试组织B”
“-测试角色B 1”
“-测试组织B”
“-测试角色B 2” 似乎是
message.append(“-”+org.getName()+”\n”)代码>在第二个循环运行时执行。这怎么可能
编辑:我用printlns测试了它,但是角色名很好。我没有触及equals()或hashcode(),我只是将字符串与equals()进行比较。问题是,当属于他们的每个角色只出现一次时,组织名称会被追加到消息中。您必须在外部循环中分配角色(这样当org
发生变化时,组织名称会发生变化)
编辑:您应该使Set roles=newlinkedhashset()代码>国际海事组织组织成员
IMO这正在工作
class TOrganization {
private String name;
public TOrganization(String name) {
this.name = name;
}
public String getName() {
return name;
}
@Override
public boolean equals(Object obj) {
if (obj != null && obj instanceof TOrganization) {
if (((TOrganization) obj).getName().equals(name)) {
return true;
}
}
return false;
}
@Override
public int hashCode() {
return super.hashCode();
}
}
class TRole {
private TOrganization organization;
private String name;
public TRole(TOrganization organization, String name) {
this.organization = organization;
this.name = name;
}
public TOrganization getOrganization() {
return organization;
}
public String getName() {
return name;
}
}
public static void main(String[] args) {
Set<TOrganization> organizations = new LinkedHashSet<TOrganization>();
Set<TRole> roles = new LinkedHashSet<TRole>();
StringBuilder message = new StringBuilder("Requested roles: " + "\n");
TOrganization orga = new TOrganization("Test org A");
TOrganization orgb = new TOrganization("Test org B");
organizations.add(new TOrganization("Test org A"));
organizations.add(new TOrganization("Test org B"));
roles.add(new TRole(orga, "Test Role A 1"));
roles.add(new TRole(orga, "Test Role A 2"));
roles.add(new TRole(orgb, "Test Role B 1"));
roles.add(new TRole(orgb, "Test Role B 2"));
for (TOrganization org : organizations) {
message.append(" - " + org.getName() + "\n");
for (TRole role : roles) {
if (role.getOrganization().equals(org)) {
message.append(" - " + role.getName() + "\n");
}
}
}
System.out.println(message.toString());
}
您的循环正在运行,您应该修复类如果每个组织只有一个角色,这是可能的。您是否正确覆盖了hashCode
和equals
?请逐步完成您的代码或添加println;你的一些假设是不正确的。从添加数据的地方开始。@凯文,或者更确切地说,他是否不正确地覆盖了hashcode
和equals
!(因为根本不实现它们就可以了。)role.getName()
必须打印org.getName()
。检查代码。不幸的是,这不是我要找的,如果我不清楚,很抱歉。我不想打印所有角色,只打印请求的角色(这些角色作为请求参数来自jsp页面)。更改集合角色是个坏主意。问题在于比较父组织。我设法把它修好了。谢谢大家!将此标记为已接受的答案。
class TOrganization {
private String name;
public TOrganization(String name) {
this.name = name;
}
public String getName() {
return name;
}
@Override
public boolean equals(Object obj) {
if (obj != null && obj instanceof TOrganization) {
if (((TOrganization) obj).getName().equals(name)) {
return true;
}
}
return false;
}
@Override
public int hashCode() {
return super.hashCode();
}
}
class TRole {
private TOrganization organization;
private String name;
public TRole(TOrganization organization, String name) {
this.organization = organization;
this.name = name;
}
public TOrganization getOrganization() {
return organization;
}
public String getName() {
return name;
}
}
public static void main(String[] args) {
Set<TOrganization> organizations = new LinkedHashSet<TOrganization>();
Set<TRole> roles = new LinkedHashSet<TRole>();
StringBuilder message = new StringBuilder("Requested roles: " + "\n");
TOrganization orga = new TOrganization("Test org A");
TOrganization orgb = new TOrganization("Test org B");
organizations.add(new TOrganization("Test org A"));
organizations.add(new TOrganization("Test org B"));
roles.add(new TRole(orga, "Test Role A 1"));
roles.add(new TRole(orga, "Test Role A 2"));
roles.add(new TRole(orgb, "Test Role B 1"));
roles.add(new TRole(orgb, "Test Role B 2"));
for (TOrganization org : organizations) {
message.append(" - " + org.getName() + "\n");
for (TRole role : roles) {
if (role.getOrganization().equals(org)) {
message.append(" - " + role.getName() + "\n");
}
}
}
System.out.println(message.toString());
}
Requested roles:
- Test org A
- Test Role A 1
- Test Role A 2
- Test org B
- Test Role B 1
- Test Role B 2